Home

VnetPC Pro Users Manual and Tutorial

1. j FS FHE Re MAIN RETURN AIR RAISE 12 DIA TO SURFACE MAIN W ETURN s e ESTOR Von A g TO SURFACE A H EAST RAR RETURN AIR DR E gt X West Bxhoust 3 Y a East Exhougt WE 9 A SS ROA Tor LZ_ A ope WEST RAR He SG PREIS a A Figure 65 Drawing of Metal Mine Airways Plan View with multiple levels active ESCAPEWAY LD EXPLORATION 42 FRESH AIR RAISE 1400 Leve 1 FRESH A AIR RAISE MAIN RETURN AIR RAISE 12 DIA BL TO SURFACE MAIN WEST RETURN VE gt a S TO SURFACE a is oe EAST RAR RETURN AIR D 3 WEST RAR 7 Mi CO MENA i FILLED STOPES 2 FILLED STOPES Figure 66 1400 Level 5 2 2 Drawing the Schematic Line Diagram When drawing the Schematic it is important to ensure that each branch is connected Do not terminate a branch and then begin the next branch without ensuring that the two are connected In AutoCAD the user should enable the endpoint running object snap to connect the branch endpoints where junctions would occur The user may develop the network using Lines Polylines and Text The Schematic will be drawn on the VENT layer while displaying both the VENT layer and the corresponding mine level basically overlaying the mine map The Schematic will be a line diagram with each line representing an airway When 72 drawing the Schematic it may be
2. W ore Open File Save File Print Undo Redo Copy Execute Simulation Execute Contaminant Zoom All Zoom In Out About VnetPC Pressure Drop Airflow Quantity 99 Allows users to open an existing VnetPC Pro File or VnetPC Pro Fan Curve File Allows the user to save all edits changes to the file Allows the user to print the current view Allows the users to undo and redo changes in the model The data will be restored in each branch by using the redo button Allows the user to copy the current selection or view and add it to the clip board This tool runs the network simulation and updates appropriate views with the results This tool runs the contaminant simulation and updates appropriate views with the results This tool zooms the extents of the schematic to fit the screen These two buttons zoom in and out as referenced from the center of the schematic shown on the screen They are useful to apply when the Zoom Tool is not active but the user still wishes to zoom the network This displays Copyright and version information regarding VnetPC Pro This setting displays the pressure drop in each branch calculated from the latest model execution shown in kPa or in w g This setting displays the airflow quantity in each branch calculated from the latest model execution shown in kcfm or m s Airflow Velocity A Resistance En Air Power Loss 5 Operating Cost el Bra
3. Branch from 92 to 50 Branch omitted in mesh selection Branch from 20 to 94 Branch omitted in mesh selection Branch from 83 to 95 Locate in Schematic x 814 z 464 Quantity kcfm Figure 48 Locate in Schematic Error List 4 4 2 Fan Results The Fan Results view lists the output operating points for the fan s in the model shown in Figure 35 It gives the operating pressure airflow parallel series configuration required power annual operating cost curve status fan status on off and a description of the fan If the user supplies a fan curve then the Fan Results view also lists whether or not the fan 1s operating on the curve The user cannot modify the Fan Results view The user may modify each fan by clicking on the Edit Fan or Edit Fan Tool under the Fan menu or by clicking on the Edit Fan icon Ol However the model must be executed again in order for changes to be updated in the Fan Results view 4 4 3 Branch Results The Branch Results view lists the output in a spreadsheet format see Figure 51 Data includes the Branch ID junction numbers airway total resistance airflow pressure drop air power velocity branch description annual operating cost and a symbol indicating whether the branch contains a fan regulator or booster fan FBR The output sheet is designed such that it is easy to read and simple to scroll through The user cannot modify the data in the Branch Results view The total res
4. 5 50 P U Typical 25 P U Seals 1 000 10 000 P U Typical 2500 P U Curtains or Brattices 1 5 P U Typical 2 5 P U Bulkheads or Stoppings 50 5 000 P U Typical 1 500 P U 17 When a new branch is created in either the Branch Input or Schematic views the default branch data type is R Resistance data type R may also be entered by using Branch Templates Please see section 3 7 for more information on Branch Template data entry 3 3 1 2 Pressure Drop and Quantity Data The p Q data input type requires pressure loss and volume flow values to be input These values are typically obtained from a pressure quantity survey using the gauge and tube method for pressure loss and vane anemometers for airflow quantity VnetPC calculates the resistance R on the basis of the Square Law as given in Equation 1 Directly entering survey data allows the user to bypass a calculation step when preparing data and helps facilitate correlation between measured airflow values and those resulting from the model simulation Equation 1 R Where R _ airway resistance Practical Unit P U or Ns m p pressure drop milli inch w g or Pa Q flow rate kcfm x 1000 cfm or m s 3 3 1 3 Atkinson Friction Factor k factor The k factor resistance data type requires the physical characteristics of the airway to be input including Atkinson Friction Factor k factor length L equivalent length of shock loss Leg if desired peri
5. 66 6 When entering nodes for a level the z value will default to the z coordinate that the user specified in the Branch Groups dialog box shown in Figure 19 Individual z coordinates may be adjusted in the Schematic view using the Selection Pointer to highlight a junction and the right mouse button to change attributes or by using the Edit Tool Another approach is to drag and drop the node when viewing the network in a section The z coordinate or the group number may be changed directly in the Junction Data view and the Schematic view will be automatically updated When working in the Isometric View 3D the tools are limited to Edit Tool Eraser Zoom and the 3D Spin Tool The Selection Pointer may also be used to select branches or edit data but the user cannot draw or move branches in the Isometric View The Zoom tool allows the user to zoom in and out of the network The 3D Spin tool is used to interact with the model by grabbing and pulling the network in order to rotate it on the screen The network can be rotated through 360 in order to find the ideal viewing perspective 3 3 4 2 Grids and Snap to Grid VnetPC features gridlines that may be plotted on the x y and z axes To access grid settings in the Schematic view the user should select Preferences gt Grid Settings shown in Figure 24 This box allows the user to enter the spacing and origin for the gridlines If the user selects a s
6. Retur Width 0 00 Symbol None Height 0 00 In Atmosphere Excluded from model execution 240 00 rea lis y Area Perlmeter Perimeter 40 00 ft Auto Calculate Length 1436 4 ft 4 Auto Length Figure 5 Branch Information Dialog Box The Branch Data Dialog box can be accessed from the Schematic view using the Edit tool or the Selection Pointer The Edit tool is chosen by selecting Tools gt Edit by selecting the Edit tool icon 4 located on the Drawing toolbar and left clicking on the desired branch The Selection Pointer may also be used Itis available by selecting Tools gt Selection Pointer by selecting the Selection Pointer icon on the Drawing toolbar or simply pressing the escape key Right click the desired branch with the Selection Pointer and choose Branch Data from the drop down menu Using any of these methods will call up the Branch Data dialog box illustrated in Figure 5 Branch types and other branch data can be changed in this view 3 3 1 1 Resistance Data The Resistance data type R requires that a resistance value be input for the branch This data type is useful for branches with a known or previously computed resistance A common example would be adding a stopping or door using an average resistance value calculated from survey data Typical resistance values for ventilation controls can have the following ranges shown in Practical Units P U Doors
7. Width 10 Ft Height 10 FE 1100 00 aa ua Area Perimeter Perimeter 40 00 ft Auto Calculate Length 1436 40 ft F Auto Length Figure 9 Rectangle Profile Type Circle Profile Type The Circle Profile Type requires only the diameter to calculate an area Maximum values for diameter are 60 meters or 200 feet The Invert Height cell represents the portion of the circular opening that is typically filled or used for another purpose For a level or slightly inclined opening the filled in portion is often times used for a road or other travel way For a shaft this 22 filled in portion can represent the other part of a split shaft for hoisting or other mine function The Invert Height cell can be input at any length less than or equal to the radius of the circle If a length larger that the radius is input VnetPC will flag the user with a warning message in place of the graphical representation Figure 10 displays the portion of the Branch Data dialog box that shows the Circle airway profile type Ainway Dimensions Profile T ype Circle Diameter 10 00 Ft Invert Height 5 00 Ft Sis 26 Bee Us Area Perimeter So een ft Auto Calculate Length 1436 40 ft 7 Auto Length Figure 10 Circle Profile Type Arched Profile Type The Arched Profile Type requires the user input width center height and rib height for calculation of the area Maximum values for width center height and rib height are 60 meter
8. 5 Software Encryption The VnetPC program is protected by a software hardlock HASP The hardlock device is installed on a USB port of the computer or server Net HASP After the VnetPC program is installed the hardlock device drivers must be installed If your PC has an active internet connection Windows may download and install the necessary drivers automatically For the single user version of VnetPC Pro the driver installation routine will be located on the installation disc for the multi user version of the program the driver installation routine will be located in a separate Net HASP License Manager directory If any problems are encountered please contact MVS MVS can be reached at phone 559 452 0182 fax 559 452 0184 or e mail at MVS at support mvsengineering com 2 6 Setup Procedure The VnetPC program is shipped as a single installation file on a CD ROM VnetPC Pro Setup EXE The following installation instructions will assist you in achieving a trouble free installation regardless of what operation system you are running or whether or not you already have a version of VnetPC installed on your machine Please note that there is an additional setup file for installing the network version on a server 1 Insert VnetPC Pro software disk into the CD DVD Drive and execute the self installing utility program from VnetPC Pro Setup exe The default install directory is C Program Files Mine Ventilation Services Inc or
9. 6894 76 N m22 Pa Pascal 1 0 inch w g inch water gauge 249 089 N m22 Pa Pascal 1 0 inch w g inch water gauge 0 249089 kPa kilo Pascal 1 0 ft w g feet water gauge 2989 07 N m 2 Pa Pascal 1 0 mm w g milli meter water gauge 9 807 N m22 Pa Pascal 1 0 inch Hg inch mercury 3386 39 N m22 Pa Pascal 1 0 mm Hg milli meter mercury 133 32 N m42 Pa Pascal 1 0 P U Resistance 1 1183 Ns42 m 8 Resistance 1 0 dbf min 2 ft44 Atkinson s k factor 1 8554 x 106 kg m 3 Atkinson s k factor 1 0 1b 1t43 density 16 0185 kg m23 density 1 0 hp horse power 745 7 W Watt 7 1 4 K Factors The following table lists commonly used friction factors for various types of mine entries The list is by far not complete however it covers a broad spectrum of the airways likely to be found in a mine The friction factors listed are the result of actual measurements taken in mines throughout the world It is left to the user s discretion to choose the most appropriate k Factor to be incorporated into the model Description of Airway SD Imperial Coal or Bedded Deposit Mines Rectangular Entry Good 0 00753 40 6 Condition Rectangular Entry Fair 0 00872 47 0 Condition Rectangular Entry Poor 0 01133 61 1 Condition Rectangular Belt Entry 0 01058 57 0 Metal Mines Single Drift Average Condition 0 00879 47 4 Single Drift Poor Condition 0 01284 69 2 Single Ramp 0 01158 0 01579 62 4 93 7 Single Belt Entr
10. Edit View Curve Tools Window Help D Wallex gt lt C Fan 3 ef PS E A A ForH Help press Fl Figure 36 Fan File Manager For each fan curve entered into the Fan File Manager a reference density for the curve and a drive frequency need to be entered When the user brings the fan curve into the ventilation model the user can elect to change the reference density of the fan In this way a fan curve that is supplied from the manufacturer at standard atmospheric density can be saved and then brought into the VnetPC program at a different density By shifting the fan operating density the fan curve will also be shifted according to the ratio of the new density but will retain the original settings from the Fan File Manager After the fan curve is imported into the VnetPC model the user may modify the frequency and density using the tool shown in Figure 39 44 Fan Curve Fan Curve Description Table Graphics Adjusted Fan Curve Points Name Joy 2 Cancel Motor Input Point Quantity Pressure Efficiency Power Description Setting 27 No kcfm in w g Remove hp Comments a moo monss esj ee Import 2 nes 8275 e an 2 p es ese f er Save Fan Configuration ee ee s saso sma es 20 efJ Fans in Parallel 1 Fans in Series Fan Adjustment Original Actual Ai Density b f 1 2 1 1 Frequency 60 50 Figure 37 VFD Fan Adjustment Wi
11. Enable auto length for all existing branches Figure 8 Automatic Branch Length Dialog Box The top section of the dialog box sets the default for any new branches added to the network If the automatic length feature 1s enabled the program will calculate the branch length based on the x y and z coordinate data of the two junctions that define the branch This feature is commonly activated when the model is created to scale from a DXF file It is important to note that VnetPC assumes that each division coordinate in Imperial units is 1 foot and in SI Units is 1 meter The units of a source DXF file must be identified correctly when imported as this cannot be adjusted afterward When Auto Length is enabled the length field will become read only or grayed out in both the Branch input and Branch Data dialog views This is indicated by changing the color of the text and fill of the field The user will not be able to edit this inactive field while Auto Length is enabled Modifying junction locations or creating a not to scale model can make viewing and manipulating the model easier The automatic length tool will update the branch length when there has been a change in the location of one of the junctions or if the branch junction numbers have been reassigned When modifying junction locations care should be taken to enter correct airway lengths by hand in order to achieve realistic branch resistance values when using the k factor
12. If the resistance type is changed to a different data format original data entered for other formats will be retained and available though inactive 15 VnetPC recognizes four branch data formats Resistance R Pressure Loss and Airflow Quantity p Q Atkinson Friction Factor k factor and Resistance per Branch Length R L A branch data format is chosen for each branch depending on available airway information The format for each branch is independent of the other branches in the model and can be changed at any time The available branch types may be accessed in the Branch Input view from a drop down list under the appropriate column for each branch as shown in Figure 4 These types can also be set or modified in the Branch Data Dialog from the Schematic view as shown in Figure 5 VnetPC Pro VnetPC PRO User Manual vdb a File GoTo Edit View Branch Tools Window Help Oe ESO BEAN B Ej gt gt Bis 2000 Level v For Help press Fl MODIFIED NUM Figure 4 Branch Input View 16 Branch Data ID 0 From 20 Group Name 1400 Level Description Note 1 Resistance Data Type pri Make Template Pressure Drop 3653 0 m in wg Get Template Data Quantity 45 50 Kcfim FaniFisedd Shock Resistance P U iW Shock Resistance Contaminants Parallel Factor 1 Cale Shock Loss Arway Dimensions Branch Parameters Profile Type Rectangle A Code
13. Intake or Exhaust with From and To nodes properly located for the program to run without errors This is not the required for VnetPC Pro This feature is not backwards compatible with older versions of VnetPC When opening a VnetPC Pro model with an older version of VnetPC if the user has the In Atmosphere selection box checked for corresponding branches the user must select the surface state in those branches as either intake or exhaust with the From To nodes properly located 3 3 4 6 Excluding Inactive Branches In previous versions of VnetPC for the user to exclude branches from model simulation he she had to put high resistance branches between active and non active areas of the schematic In VnetPC Pro the user simply has to check the box labeled Excluded from model simulation in Branch Data dialog to deactivate branches from simulation The user may also change the activation status of branches in the Branch Input view by selecting No or Yes under the column labeled Excluded 3 3 4 7 Branch Colors VnetPC Pro allows the network to be color coded according to the type of airway as well as parameter range Branch colors can be enabled by selecting the following three options under the Preferences menu No Color Use Color Range or Use Color Code No Color turns all features to the selected foreground color Use Color Range refers to the specific color ranges allocated to the parameters quantity vel
14. N f REFUGE STATION Pt 3 920 in wg No 1 FRESH AIR RAISE 4 Shotcrete Bulkhead WEST RETURN AIR RAISE MAIN RETURN AIR RAISE Figure 69 1800 Level with Wire Frame Drawn 74 1920 Leve R RAISE 1920 B STOPE Figure 70 1920 Level with Wire Frame Drawn Hoist Shaft a So IN Y UP TO 1920 1 o EF MAGUS T a Fast Exhaust 2000 E Sto A ae 2000 A Stopes y Figure 71 2000 Level with Wire Frame Drawn After the line diagrams are established for each level the ramp is then identified VnetPC does not treat each of these layers as a distinct level although in some cases it can be thought of in this manner Instead each layer imported to VnetPC is identified as a Group of branches with similar general characteristics When all of the branches have the same general elevation then they can be considered a Level However since a ramp will have various elevations for each 75 set of branches it may be easier to think of them as a Group The branches drawn for the ramp are shown on Figure 74 Figure 72 Close up of Branches Drawn in Ramp The ramp is traced using large line segments Wherever the ramp connects to a level the schematic wire frame is connected to the intersection previously drawn as displayed in Figure 75 76 xnNausT Figure 73 Ensure all Branches are Con
15. ST hn ae 6 Line Plot Figure 21 Cross Section View of a Metal Mine The Plan View Long Section View Cross Section View and Isometric 3D can illustrate all of the groups selected groups or only the active group The groups are designated in the Branch 33 Groups dialog box illustrated previously in Figure 19 The network can be manipulated in each of these views The user can select the background color for the Schematic view by selecting Background Color under the Preferences drop down tool menu The background colors are white light gray gray dark gray and black with the foreground in black or white The Background Colors dialog box is shown in Figure 22 The selected background color will be retained for the saved current model If the user creates a new model the background color will be the defaulted color of white with the foreground of black Background Colors Foreground Background Black white Sample Figure 22 Background Colors Dialog Box The user can select which group is active using the Branch Groups dialog box or the drop down menu located on the toolbar in the Schematic view The user can see which group is active because it will be shown in the drop down box on the toolbar The option of viewing a single group allows the user to work with just that level in Plan View Long Section View or Cross Section View When using the Plan View Long Section View Cross Section View or Isom
16. Template gt Select Fields in the Branch Template view This feature will only modify the selected fields For example a user creates multiple branches with varying resistance data types but would like to modify the Branch Code of each branch to a single value without altering other fields The user will select to apply the Branch Code and ignore the other available fields Jl Template Fields Select Fields to Apply Available Fields Fields to Apply Description Apply gt gt Type Resistance Length Friction Factor Braneh Code Resistance perLength lt lt Ignore lt lt Ignore Area Perlmeter Parallel Factor Auto Length Symbol Apply All gt gt Apply All gt gt Group Name Display Parameter lt lt Ignore All Ignore al Airway Profile Diameter Figure 44 Branch Template Fields Selection Dialog Box New Branch Templates can be added to a ventilation model in the Branch Template view New Branch Templates may be created or deleted by selecting Template gt Add Template or Delete Template respectively Branch Templates based on existing branches can also be created in the Schematic view and the Branch Input view To apply a template in the Schematic view a user may select a branch or branches using the Selection Pointer tool Using the Selection Pointer right click on a selected branch and choose Apply Template or Make Template Apply Template allows the user to apply
17. Ti id 64 FIGURES S JONCTION DATA VEW carena aa aa O E TNO 65 FIGURE 59 DXF SELECT INFORMATION DIALOG BOX cc cece cceccsecccssccesccesccecceusccusccecceusceusccesceusccusccesseusceuceuaes 66 FIGURE 60 COLUMNS DIALOG BOX FOR BRANCH INPUT VIEW cccccsecccscccscccssccuscccssccesccescsesceusccuscesseusseuceenes 67 FIGURE 61 SELECTED BRANCH GROUP BEING DISPLAYED IN BRANCH INPUT VIEW 0cccsccssccscccsccesccesccescensees 67 PE VN UNO VIN atar ata one antes Rona eaeceisapuastceod aren loa cian dies 68 FIGURE 03 CASCADE WINDOWS sas A A A A dd 69 FIGURE 04 TIEE WINDOWS visi A ie nuseda diane Medewaooasomen we andeg 69 FIGURE OS ARRANGE ICONS dorana a ad O A a 70 FIGURE 66 AUTOCAD LAYER PROPERTIES MANAGER DIALOG BOX COPIED FROM AUTOCAD 2010 71 FIGURE 67 DRAWING OF METAL MINE AIRWAYS PLAN VIEW WITH MULTIPLE LEVELS ACTIVE ccconccccnonoccnnnnoccnnno 72 FIGURE 605 T400 EE VEL iras 172 FIGURE 69 1400 LEVEL WITH WIRE FRAME DRAWN cccccscccssccsscccscccsccesccescceusccesccescceesseesccesseeusceusscessseusceusccenss 73 FIGURE 70 1600 LEVEL WITH WIRE FRAME DRAWN sicioibakiesk iia nied sen nbs aela 74 FIGURE 71 1800 LEVEL WITH WIRE FRAME DRAWN oo 74 FIGURE 72 1920 LEVEL WITH WIRE FRAME DRAWN renent ied iene ai 75 FIGURE 7322000 LEVEL WITH WIRE FRAME DRAWN seioisoohies esac inh o ao 75 FIGURE 74 CLOSE UP OF BRANCHES DRAWN IN RAMP ccsccsscsscssccsccsccsccsscsscscescescessesscsscscescescesse
18. all Ee IN ETE E E ide ar Figure 19 Branch Groups Dialog Box From this view the names and default z coordinates of any group can also be modified Within the Branch Groups dialog box the user can select which levels to Show or Hide and which group is Active The Active group is in bold text and is on which new branches or text can be added The level system allows the user to digitize the network in plan view on a level by level basis which simplifies the construction of a complex 3D mine VnetPC incorporates multiple choices in viewing perspective for the network La Plan View Long Section View i L Cross Section View E Isometric 3D View Active Group Level Selected Groups Levels All Groups Levels Edit Groups Levels Dialog Box 32 Two of the views are illustrated in Figure 20 3D and Figure 21 Cross Section The active perspectives may be selected in the Schematic view from the View drop down menu or by selecting an icon on the toolbar vue File GoTo Edit View Preferences Zoom Tools Window Help CORA ERC SGUR BSB x 7 RER SAQOZSRPLLL BBS gt Sle zm KN Ww ETE FT lt LJ For Help press Fl Line Plot Figure 20 3D View of a Metal Mine with 3D Spin Tool Active 7 VNEL D netrC PRO User Jalwdb Schematic w File GoTo Edit View Preferences Zoom _Tools Window Help OsE4 o B 8Aa BOMR HS B x 7 WKF SAQoz2 HfL GL Feo Sez y TV
19. allowed only one branch at a time to be altered in the Schematic view A branch could be deleted and the Branch Data Dialog box could be accessed to modify branch parameters VnetPC Pro supports editing multiple branches through multiple branch selections and branch templates Branch selection is indicated by an increased line width Line width and line highlight selection settings can be altered by selecting Preferences gt Line Properties in the Schematic view Line properties are further discussed in Section 3 4 5 1 Branches can be selected by placing the cursor over the branch and clicking the left mouse button A branch is deselected when the Shift key is held down and the branch is clicked on again The branch selection is cumulative selecting new branches will not change the selection status of branches that have already been selected The entire selection can be aborted by hitting the Esc key at any time Multiple branches can be selected simultaneously using selection boxes A selection box is started when the left mouse button is pressed and held while the cursor is dragged across the screen The selection box closes and the selection is made when the mouse button is released A selection box generated from left to right will select all the branches entirely contained within the box Both branch junctions must be included for the branch to be selected A selection box made by moving the cursor from right to left will
20. and R L data formats This is especially important for branches used to represent shafts and raises The lower section of the Automatic Branch Length Calculation dialog box allows changes to be made to existing branches The default is set to Make no changes If the user selects to enable the automatic length feature for all existing branches the length of all existing branches will be updated to the respective computed values Any existing length data will be overwritten and is not retained Disabling the auto length feature prohibits branch lengths from updating if junctions are moved Branches retain their most recent length prior to disabling the auto length feature If branches had the automatic length feature enabled prior to disabling the feature that branch will continue to retain that length until the user manually changes it During unit conversion the length of branches is converted automatically regardless of Auto Length status The coordinates in the Schematic view are also converted resulting in updated length data from the automatic length feature 21 3 3 1 6 Auto Calculate Area Perimeter Tool The VnetPC program incorporates an automatic area and perimeter calculator tool based on airway dimensions This feature can be activated for each branch by checking the appropriate box in Branch Data dialog in the Schematic view or the appropriate column in the Branch Input view In order to calculate the proper area the user must p
21. determine these parameters along with good engineering judgment 7 1 11 1 Example Design Criteria The following 1s an example of elements which might be included for consideration in design criteria e Dilution of hazardous gases to concentrations below statutory or administrative concentrations e The oxygen content in any airway accessible to personnel should not contain less than 19 5 e The carbon dioxide content of the air in any airway accessible to personnel should not contain more than 0 5 109 e The minimum air velocity experienced at any place in the mine should such that turbulent flow is maintained e Identify maximum air velocity based on airway types and economic considerations 7 1 11 2 Suggested Maximum Airflow Velocity e Provide sufficient air to working faces and last open cross cut to exceed statutory minimums and to meet actual needs these are usually greater than the statutory minimums e Underground shops compressor stations and battery charging stations should all be ventilated directly to an exhaust airway e For generalized planning where particulate emissions are not of concern diesel equipment should be ventilated with at least 125 cubic feet per minute of air standardized per brake horsepower The actual elements of the design criteria will vary with respect to the mine type mine layout and method types of equipment and a host of other special considerations Local laws regulations and pract
22. either zoom in or zoom out within the Schematic view The user can also select a window to zoom by engaging the Zoom Tool under the Tools menu Once a window has been zoomed it can be reduced by using the Previous or All command on the Zoom menu The Previous command zooms to the previous level The All command resizes the extents of the network to fit on the screen There is also a Zoom All tool button present in the Schematic view Panning from one portion of an enlarged Schematic to another can be accomplished by utilizing the scroll bars arrow keys on the keyboard or pressing down the center mouse wheel When panning the program will redraw the Schematic between each pan 4 4 6 Junction Data In order to display or print the on screen Schematic coordinates must be assigned to each junction Coordinates are either entered manually or copied from a spreadsheet into the Junction Data view see Figure 58 imported from a DXF file or digitized using the system 64 pointer within the Schematic view In the Junction Data view the junction numbers appear on the left column and X Y and Z coordinates are shown in the adjacent three columns The column marked Branches Attached indicates how many branches are connected to each node Within this view the user may also add a junction by selecting Junction gt Add Junction Junctions may also be deleted in this view by selecting Junction gt Delete Junction It sh
23. in the calculation but are not shown in the Schematic view Line Properties This command allows the user to change the visual thickness of the branches as displayed in the Schematic view and printed in terms of pixels as illustrated in Figure 56 The Highlight function allows users to increase the thickness of branches when selected or otherwise active This works by applying a user defined Plus value to the line width defined for the whole model The Highlight function can be used based on the Selected Branch Active Group or Contaminates The default line width is 1 pixel A line width value of O will result in an applied value of 1 pixel The default highlight value is 2 A highlight plus value of 0 may be entered but is highly discouraged as the user will be unable to visually distinguish selected branches An example of the Highlight function is shown in Figure 57 Line Highlight Highlight a Selected Branch Cancel Active Group Contaminants Plus A Pixels Line Width Screen Pixels Printer Pixels Figure 54 Line Highlight Dialog Box 63 VnetPC Pro VnetPC PRO User Manual ete File GoTo Edit View Preferences Zoom Tools Window Help osas EAS jFeBSAQ A Z A a M Aja Elx 7 h Edi E B e gt A 8 2000 Level we VnetPC PRO User Manual Schematic For Help press Fl Line Plot Figure 55 Example of Line Highlight 4 4 5 2 Zoom Menu With the Zoom command the user can
24. length tool 19 branch attributes 93 branch code 63 branch data formats 15 branch input 11 branch input view 14 15 18 20 24 25 27 38 41 52 68 90 branch results 11 branch results view 59 branch template 53 circuit 12 color 63 color code 37 colors 38 columns 68 contaminant distribution 52 contaminants 11 conversion 14 convert 56 coordinates 12 create a new VnetPC file 72 create branch 26 create fan 26 create junction 25 create label 26 data preparation and input 11 data type 1 16 data type 2 17 data type 3 17 data type 4 18 descriptive information 13 drawing a schematic 75 dual parameters 61 62 DXF file 68 DXF import 12 edit tool 26 enter the schematic 12 eraser tool 26 errors 57 99 establish a ventilation schematic 72 execute simulation 56 fan curve 42 45 fan file manager 45 fan input and fan results 11 fan input view 41 fan results view 59 fixed quantities 11 96 fixed quantity 49 fixed quantity view 60 font sizes 64 gasflow 52 getting started 72 goto menu 11 gridlines 34 group 30 hasp 8 import 56 import DXF 35 inject 49 input 11 junction data 11 junction data view 66 junction numbers 12 junction range 64 114 Kirchhoff s Laws 7 label 28 level 30 model information 11 model information view 13 nethasp license manager 9 orifice area 14 parallel b
25. necessary to choose either SI or Imperial units provide an average air density and power cost and identify the surface reference node number 7 1 8 Importing from Old VnetPC Files VnetPC Pro allows import of old VnetPC files from earlier versions of VnetPC The user has the option under the File menu of importing files from the previous version and converting them into 107 VnetPC Pro format When saving the resulting data the user will then save the file in the vdb format To convert files chose Open under the File menu When the file type s have been chosen the user selects the OK button to progress to the file specification dialog box In this box the user can either directly type a source file in each window or can browse through various directories and different drives in order to locate files When the desired file has been selected click OK to initiate the file conversion process Remember to execute the simulation immediately after the data files have been converted and saved in the Windows file format Failure to execute the program will lead to erroneous data generation and fan results in the output views During conversion of the coordinate data file VnetPC will snap the x y coordinate values to the closest tenth of a unit Version 3 1 did not round coordinate data values subsequently during conversion small discrepancies can occur For example if two nodes on the same level have y coordinates of 20 04 and 20 05 th
26. other as specified by the user The installation process creates the directory and inserts the associated program and ancillary files When the installation is complete a shortcut for VnetPC Pro will appear on the desktop 2 Plug the HASP key tag into a USB port Windows should automatically install the latest device drivers for the HASP key if your computer has an active internet connection If Windows does not install the HASP device drivers automatically the device drivers can be found on the installation disc or at our website www mvsengineering com Once the installation of the HASP device drivers is complete a red light will activate in the HASP key tag The red light will remain on as long as the HASP key tag is plugged into the machine and is functioning properly 3 Click on the shortcut to start VnetPC Pro a The program should open b Select File gt New gt VnetPC Pro File sequence to open a new model illustrated in Figure 1 10 VWnet PC Pro File VnetPC Pro Fan Curve File Figure 1 New Model Creation c Next a dialog box should appear as shown in Figure 2 requesting you to select the system of units for this model Select units desired for your model and press OK Select Units Please select the system of units for the document Figure 2 Unit Selection Dialog Box d If you get an Untitled Model Information dialog box the program and the associated support programs are in
27. per Length Values Dialog Box The Select R per L feature allows the user to enter an R L value and description for each variety of airways to be modeled with the R L data type These stored values can then be recalled to populate resistance data for future branches The Select Resistance per Length dialog box can also be accessed in the Branch Input view from the Branch drop down when an R L field is selected An additional way to access the stored R L values from the Branch Input view is to double click on the edge of the spreadsheet cell for the R L value of a desired branch Resistance per unit length data type R L may also be entered by using Branch Templates Please see section 3 7 for more information on Branch Template data entry 3 3 1 5 Automatic Length Tool The VnetPC program incorporates an automatic length tool to provide a length value based on junction coordinates This feature can be activated for each branch through the appropriate column in the Branch Input view and through the Branch Data dialog in the Schematic view Universal settings for this feature can be adjusted by selecting Tools gt Auto Length in most views This displays the Automatic Branch Length Calculation dialog box as shown in Figure 8 20 Automatic Branch Length Calculation Default for New Branches Enable auto length for all new branches Reset Existing Branches Make no changes Disable auto length for all existing branches
28. per length for this timber cribbing a graph has been plotted of resistance per length against entry height EJ Lr bo E Stand esis per Mieter Hs vm x 107 Ln Ln 17 18 19 20 21 22 23 24 25 26 27 328 2 Entry Height mu 7 1 5 2 Resistance per Length for Intake Gate Roads This chart can be used to determine the resistance per unit length for longwall or miner section gate roads The chart reads the standardized resistance per meter value vs average entry height for single airways in SI units The resistance per unit length value for multiple entry gate roads can be calculated by dividing the resistance per length value by the square of the number of entries 105 1 7 1 5 2 1 23 25 2 7 2 9 3 1 3 3 Entry Height im This chart was established as the result of field measurements taken at various mines with different mining heights 7 1 5 3 Resistance per Length for Longwall Faceline This chart can be used to determine the resistance per unit length for a longwall faceline The chart reads the standardized resistance per meter value vs average wall height for single airways in SI units The resistance per unit length value for multiple entry gate roads can be calculated by dividing the resistance per length value by the square of the number of entries O D ER a D p o stand Kesis per Meter Ha x 10 a 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 Wal Height im Note Min
29. place the labels on the top left top middle top right bottom right bottom middle and bottom right locations on the printed document The user may also opt to turn the plot labels off by selecting Off Default Font This command is similar to other Font tools in common text writing software such as Microsoft Office etc It enables the user to choose the desired font font style size effects such as strikeout and underline color and script Junction Nodes This command toggles the junction nodes on and off in the Schematic view This is helpful when branch values and node numbers become cluttered Removing the junction nodes may help to clarify the drawing Junction Numbers This command toggles the junction numbers on and off in the Schematic view This also is helpful when branch values and node numbers become cluttered Relative Pressure The relative pressure is given in square brackets next to each junction This feature is now available to be toggled on and off in the Schematic view and does not have to be tagged during execution as with previous versions of VnetPC 62 Symbols This command toggles on and off any symbols the user has specified in the network Display Labels This command toggles on and off the labels created in the Schematic view Show Inject Reject Branches This command toggles on and off any inject reject branches that the user has specified in the network The branches are still included
30. profile type cross section shock resistance airway dimensions and branch code color Symbols include bulkheads stoppings doors brattices and regulators Airway profiles include rectangular circular and arched cross sections In addition to the descriptive data each branch can have a resistance assigned to it through this dialog box One of four methods R P Q k Factor and R L can be used to assign or calculate the resistance for each branch by selecting from the drop down list Branch Data ee ID BG From 43 To Swap From To Group Name 1800 Level Cancel Description Note 1 Resistance Data Make Template m r Pressure Drop ow i Get Template Data k Factor O A A A A Fan FinedG Quantity pa shock Resistance 0 P U v Shock Resistance Contaminantes Parallel Factor 1 Calc Shock Loss Away Dimensions Branch Parameters Profile Type Rectangle me sw A Code Active Width 10 Ft a Symbol None Height 10 Ft Fl In Atmosphere Excluded from model execution Area 100 00 Ue y rea Perimeter 7 Perimeter 40 00 ft Auto Calculate Length 601 5 ft 4 Auto Length Figure 95 Branch Data Dialogue Box When entering resistance data for k Factor or Resistance per Length R L a tool Auto Length has been incorporated that will calculate the lengths of the branches according to their coordinate positions in
31. program a contaminant can be traced through the network This contaminant is added to the network by selecting the icon on the Toolbar or selecting Tools gt Contaminant A contaminant is inserted by selecting the desired branch with the contaminant curser the Branch Contaminants dialog box Figure 102 will be displayed on the screen In this dialog box the emission rate of the contaminant can be identified or the concentration of the contaminant in that branch can be inserted Branch Contaminants ID 66 From 43 Description Surface State Neither Air Quantity 49 21 kefm Data Threshold 0 005 Default Value 0 005 Emission Rate 0 Ectfrn Emizzion Concentration Contminant Flow Contaminant Concentration Figure 100 Contaminant Dialog Box The downstream steady state concentrations and flow rates of the contaminant will be calculated for all affected branches 5 8 Program Execution Once the model is established the user should execute the simulation After successfully simulating the mine ventilation system the user can export the schematic back into AutoCAD through a DXF file to provide an overlay of the projected ventilation values The user can create a DXF from the schematic by selecting Tools gt DXF File in Schematic view Once selected the user will be prompted with a save as screen to save the file as a DXF 95 During the program execution any simulation errors d
32. select all branches that have at least one junction contained by the box Branches can also be deselected using selection boxes when the Shift key is held down 30 To apply an action to multiple branches place the cursor over one of the selected branches and click the right mouse button to access the branch functions Only Apply Template and Delete Branch es will modify the entire selection Multiple branches can also be deleted using the delete key If any of the other functions are selected including Make Template only the branch that was selected will be modified or used When modifying multiple branches a Selected Branch List will open to display details about the current selection and allow the user to continue or cancel the operation as shown in Figure 18 This will prevent accidental deletion or modification if an entire group was recently activated changing the active group will automatically select and highlight all the branches in the group This will also ensure that the selection is correct and does not include branches that were thought to be deselected previously Selected Branch List BranchiD From 1400 Level Cancel 1400 Level 1400 Level 1400 Level 1400 Level 1400 Level 1400 Level 1400 Level 1400 Level 1600 Level 1600 Level 1600 Level 1600 Level 5 B 7 E F 4 3 1 31 30 29 29 Hltemz 75 Figure 18 Selected Branch List 3 3 4 1 Levels and Perspective VnetPC ha
33. selecting Tile all open windows will arrange themselves in a tile like format see Figure 64 Jser Manual Fan Results Fan Fan Operating xAAAAAAAAAAoo _ _ o_o _ ______ __ o No From Binks Quantity oie Cost ries in w g kcfm hp Siyr OT aaa a 7818 31443 O As meses 20340 ares ZN an bE Bian aaa wg a so noj aoj 2 001 o C 36870 2490 0 e 00 2 3584 4 No Taa E e670 noo m3900 s osea mo Quantity kcfm Resistance P U x 3480 4 oosa2 1068 62 BEA eee Quantiy Emission zm oi 897 2 kcfm kcfm 11 35 E O ep aw moss asooo sos ass e ap 2 ap sp we o E 3 Rp ap esp A OA gt TT msj 7 a 4 Pi caen m in wg Figure 62 Tile Windows 69 If the user selects Arrange Icons all minimized windows will arrange themselves in order across the bottom of the screen see Figure 65 To Edit View Preferences Zoom Tools Window Help LDL PBS o Blatter O y CEREZA D Hgo Ema RFR BRSAQRALZ YE Figure 63 Arrange Icons 5 Tutorial 5 1 Introduction This tutorial describes how to establish a ventilation model in VnetPC using AutoCAD or a DXF file generated by another mine planning or CAD package to establish a network Schematic Additional help about other VnetPC features can be found in the Contents selection of the Help menu in the VnetPC program The following sections detail how to est
34. shown in Figure 13 If the user wants the reversed airflow to be the new direction of flow the reversed airflow symbol may be removed To do this the user selects Tools gt Normalize Quantity and then selects Tools gt Execute Simulation This will remove all reversed airflow symbols Normal Airway Reversed Airway Figure 13 Example Airways If desired the ventilation network may be developed entirely within the Schematic view Networks are established using functions obtained from the Tools menu or Tools Bar This menu allocates different functions to the selection pointer The following list of functions is available bi Selection Pointer E Create Junction 26 Create Branch Plot Existing Junction Create Fan Create Contaminant Create Label Zoom Tool Pak tT a Eraser Tool Edit Tool 3D Spin Tool SINS The Selection Pointer is the default option This allows the user to highlight branches and by pressing the right mouse button change the attributes of those branches and access Template features The network may also be resized or adjusted by dragging nodes around the screen using this pointer selection pointer will be restored when the Esc key is pressed The selection pointer can be used in all four model views plan view cross section long section and isometric The Create Junction option allows new junctions to split existing branches The creation of junctions is nor
35. the Schematic view This will only work for schematics that have been drawn to scale When entering resistance data for which a length is required in only a few branches the Auto Length box can be selected to enable it If an entire network is being developed then the Auto Length can be set to globally edit new or existing branches by selecting Tools gt 92 Auto Length A dialog box will appear as shown in Figure 98 the user will need to select a default for all new branches created or make changes to all existing branches The length of each branch will be updated automatically as junctions are moved or added to the schematic Automatic Branch Length Calculation Default for New Branches Enable auto length for all new branches Reset Existing Branches Make no changes Disable auto length for all existing branches Enable auto length for all existing branches Figure 96 Automatic Branch Length Calculation Dialog Box 5 6 Inserting Fans and Fixed Quantities Once the attributes for each branch have been entered the next step is to add fans or fixed quantities in the ventilation model These can be rapidly input to the model in the Schematic view however they may also be added in the Branch Input Fan Input or Fixed Quantities views To insert a fan select Fan or Fixed Q from the Tools menu use the Fan or Fixed Q icon on the Toolbar or right click with the pointer and select Fan Fixed Q from the drop down m
36. the first time or when utilizing the Save As command under the File menu When a file is saved the program automatically prompts for the extension vdb VnetPC supports extended file names 14 3 2 2 Units and Conversion Utility VnetPC supports both Imperial and SI units The user must initially specify one type of engineering unit however should the user decide to change units an automatic conversion feature 1s available This conversion feature is available from the Tools menu in any view except the Model Information view In the Model Information view there is a Units tab that allows the user to switch between units This is the equivalent of the Unit Conversion feature in the Tools menu for other views The conversion utility converts all the input data including the fan curves It is important that the user executes the program following unit conversion In rare cases during conversion one or more data values may become out of range and the program will truncate the values However this will only occur if the original network contains extremely high input parameters and the truncated values should still be sufficiently large so that network accuracy 1s not impacted 3 2 3 Power Cost The user should enter an electrical power cost to determine the operating cost for the system fans Power costs are provided in unit k Wh where the unit may be any currency 3 2 4 Air Density and Regulator Sizing and Shock Loss Calculato
37. to find the appropriate DXF file When the user selects a DXF file VnetPC will examine the file for available layers and then prompt the user to select a layer to be used as shown below in Figure 26 The imported layer will create a new Branch Group defaulting to the name the user specified for the imported layer 36 The user has the option to select a default branch type The selected default branch type will be applied to all new imported branches created for the selected layer Branch type can be altered quickly following DXF import using Branch Templates The units drop down menu is utilized when the DXF file and VnetPC model have different units For example if a VnetPC model is developed in Imperial units but the DXF files are in SI units the user will select SI units on the Layer Selection dialog box This function will convert the DXF files units to the VnetPC model units Layer Selection Layer Name Default Branch Type A ka Figure 26 DXF Import Layer Selection Establishing a suitable DXF file requires a program that supports layers such as AutoCAD The user should develop the network in the CAD program using only Lines and Polylines If another object type is created such as text or hatching in a layer with lines and polylines only the lines and polylines will be imported to VnetPC Also layers without lines or polylines will not be shown in the Layer Selection dialog box The network should be developed on a
38. 000 iterations a balance has not been reached the program terminates and the values obtained after the 1000 iteration are listed as the results in the output This error is most often caused by excessive use of very high resistance branches The network data should be checked and the Schematic viewed to identify any erroneous branches The iteration limit is set in order that the computer does not spend excessive time performing iterations trying to resolve an unsolvable network 4 4 1 5 Locate Error in Schematic Tool In the event an Error List dialog box appears after execution the user may highlight the error in the list and select Locate in Schematic The selected branch in the error list will become highlighted as shown in Figure 50 The error list will remain on the screen to assist the user with locating the errors in the ventilation model 56 E VnetPC Pro VnetPC PRO User Manual File GoTo Edit View Preferences Zoom Tools Window Help DSAHS gt o alexa 0 1 PON ars RF KRESAQRIALZ Es ty EP Be o 8 2000 Level y we VnetPC PRO User Manual Schematic Error List x Total Number of Errors 9 OK Errors Cancel Too many fixed quantites Branch from 30 to 33 No mesh found for branch Branch from 10 to 20 No mesh found for branch Branch from 20 to 22 Branch omitted in mesh selection Branch from 10 to 20 Branch omitted in mesh selection Branch from 20 to 22 Branch omitted in mesh selection
39. AutoCAD drawing no branches were given for the intake and exhaust shafts These can be added directly in VnetPC the junctions should already exist on the levels 86 5 3 2 3 Viewing and Editing the Schematic in 3D The VnetPC program incorporates a feature that allows the user to view and edit Branch and Junction data in 3D isometric The user can actively rotate the schematic and zoom in out on the schematic To switch to the 3D perspective the user selects the 3D view icon from the tool bar The schematic can be rotated by using the 3D Spin Tooli The user can drag and drop with the mouse to rotate the schematic If portions of the schematic rotate off the edges of the screen the user can automatically resize the schematic to fit the screen with the Zoom All icon located on the tool bar or by scrolling the center mouse wheel To edit branches the user can right click using the selection pointer or 3D Spin Tool on the desired branch Figure 90 shows the schematic rotated to allow the branches to be viewed and edited more clearly Figure 88 Rotated 3D Schematic 5 4 Adding Branches to the Schematic Branches can be added to the ventilation model directly in the Schematic view or in the Branch Input view Branches that are added through the Schematic view will automatically show up in the Branch Input view with resistance values defaulted to zero The user selects the Create Branch option located under the Tools menu or th
40. CONTAMINANT DATA VIE Wairi e a ad e S 50 FIGURED BRANCH TEMPLATE VIEW urarea a a a a a cod ES 51 FIGURE 46 BRANCH TEMPLATE FIELDS SELECTION DIALOG BOX ooccnnccnnnccnoccnnoconoronancnnnconaronancnnnronaronancnunccnaronaninnns 52 FIGURE SELECT TEMPLATE DIALOG DO ao 52 FIGURE 48 TRANSIENT TIME CALCULATOR DIALOG BOX ooocccncccnoconiccnnocnnaconenonnncnnaronancnnoconoronancnnnronaronnncnnnccnaronaninnns 54 FIGURE 49 VIEW ERRORS DIALOG BOX 0ooccncccnoconcnccnnncnnoconaconnncnnnronaronnncnnnronnrcnnnronronnrcnnronnronnncnnronaronnrcnnnccnarcnuncnnns 55 FIGURE 50 LOCATE IN SCHEMATIC ERROR LIST oooccnnccnnccnniccnuncnnnconaronuncnnnronarcnnncnnoronnrcnnronoronnncnnnronaronnncnnccnarcnnncnnns 57 FIGURE 51 BRANCH RESULTS VIE W cooccnnccnnocnnoconiconnncnnoronaronnnconaronnrcnnnrnnnronnrcnnnronro nunc nnnronnronnncnnnronaronnncnnnccnarcnanonnns 58 FIGURE 52 PARAMETER QUICK SELECT TOOL BAR Q ccccccccccccesscccessecccesccseuseccccusecsceusccseeecsseusecssuueecesenecseeueeseeees 59 FIGURE 53 SELECTING DUAL PARAMETERS IN THE SCHEMATIC VIEW cccccscccseccscccssccesccesccecccusccusccensceesceuseeucs 60 FIGURE 54 SELECT DUAL PARAMETERS DIALOG BOX occcnccnnoconnnccnincnnncnnaronancnnaconoronancnnronaronnncnnnronaronnncnnnccnarcnuncnnns 60 FIGURE 55 EXAMPLE OF DUAL PARAMETERS DISPLAYED ON A VENTILATION SCHEMATIC ccsccseccsscesceeeceesees 61 FIGURE 50 LINE HIGHLIGHT DIALOG BOX nacida ii di id 63 FIGURE S7 EXAMPLE OP LINE HIGHEIGH
41. Color_5 Continu efa Color N Descriptio E Es ge E E Es Eg Es ES E TI m ee e i a ah e e Eh E Eh Ey E E Eh Ep L 1400VENT 1600 Level 1600WENT 1800 Level 1800WENT 1920 Level 1920WENT 2000 Level 2000VENT Ts da do do de do do dh dodo qh Ts Continu efa Color_5 aD D 60 0 0 0 o OR 0 BERR T F a a i e a a a 7 1 Yy G g Alii layers displayed of 11 total layers Figure 64 AutoCAD Layer Properties Manager Dialog Box copied from AutoCAD 2010 Each of the layers denoted with the suffix VENT will contain a portion of the overall Schematic When transferring the Schematic to VnetPC each level must be individually imported Because VnetPC uses the digital exchange format DXF it can import files from other software applications An example metal mine is shown below with each layer turned on to show how they overlay This procedure can be done with multiple files one for each level however it can be more efficient to develop a mine map in one DXF file with multiple layers as shown on Figure 67 Figure 68 shows a single level of the mine This level will be used to start a Schematic drawing 71 Holst Shaft SuiistT SHAFT q EXPLORATION VENTILATION LEGEND eS a 2 FRESH AIR O Level 400 tevel
42. Emission Contaminant Contaminant Rate Concentration Flow Concentration kefm T ikcfm Quantity kcfm 0 00000 0 00000 Figure 42 Contaminant Data View Identifying the branches representing the location of the contaminant emissions lets the user specify the sources Under the Contaminants view the branch numbers junction numbers branch quantity and branch description will appear the same as in the Branch Input view These values cannot be changed in the Contaminants view Contaminant sources are entered as quantities or concentrations in the various columns Valid entries for emission rate must be positive and less than 10 0 kcfm or m s Data can be entered to four decimal places Contaminant data is entered in the Schematic view using the Contaminant Tool and clicking on the branch where the contaminant will be added The input concentration represents the concentration of the emission at that point in the airway The user should not enter the total 50 contaminant concentration which will include any upstream sources this value is computed by the program The contaminant distribution analysis routine requires that branches representing intakes carrying fresh air directly from the surface be identified VnetPC uses those branches selected as Intake from the Branch Input and Schematic views used for mesh closure as well as contaminant analyses The contaminant execution is conducted by selecting Tools gt Execute Co
43. Figure 101 a gt Fan Curve Fan Curve Description Table Graphics Adjusted Fan Curve Points Name Example E Motor Input Quantity Pressure Efficiency Setting 15 de Power Des TERRE p i E np E Comments 3000 1700 40 a A Save Fan Configuration Fans in Parallel 1 Fans in Series 1 Fan Adjustment Original Actual Air Density Ib fF 0 075 0 075 Frequency 60 60 ICICI aj fr fr fos J win jo Jin e L a G Figure 99 Fan Curve Dialog Box 94 The individual properties of the fan are entered in the Fan Curve dialog box A maximum of 20 points are allowed to be input for each curve It is generally a good idea to cluster the greatest number of points along the operating section of the fan curve The program will linearly interpolate between each of these points Once the fan curve is entered select OK The Save and Import tools refer to the Fan File Manager By selecting Save the fan curve will be saved to an existing fan database and can be used in any model in the future by selecting Import This removes the task of continuously developing the same fan curve for different models Once the fan curve is entered in the dialog box select OK The fan curve will then be incorporated into the model It is not necessary to select Save 5 7 Adding a Contaminant In the VnetPC
44. IGURE 92 ILLUSTRATION OF A SINGLE GROUP LEVEL AND GROUP FILTER cccccseccseccescccseceecceseceseseesceeseseees 89 FIGURE 95 INSERTING Acd UNC TION ainra A AAAA dia 89 FIGURE 94 BRANCH DATA DIALOG BOX cut dida 90 FIGURE 95 LOCATION OF BRANCH CODE IN DROP DOWN MENU cccccsecccscccsccesccescccusccescceseceuscceceeeceusceusceeaes 91 FIGURE 90 BRANCH GC ODE DIALOGUE BOX 0 A ao 91 PIGURE 97 BRANCH DATA DIALOGUE BOX 2 to 92 FIGURE 98 AUTOMATIC BRANCH LENGTH CALCULATION DIALOG BOX ooccnccnnccnoconccnnconaconoconccnaronocnnconaconocnnronaconocnn 93 FIGURE 99 FAN OR FIXED QUANTITY DIALOG BOX cccccceccccsscccesecceececeecccesccceecceecseeececenecteeceeueceseneceeneceeneceees 93 PIGURE TOD FAN DATA DIALOG BOX a a A oia 94 FIGURE IOL PAN CURVE DIALOG BOX ao 94 PIGURE 102 CONTAMINANTIDIAEOGDOX tdt 95 List of Equations EQUATION 1 EQUATION 2 1 Introduction Welcome to VnetPC Pro This latest upgrade of the popular ventilation simulation program combines the input of ventilation and mining engineers from around the world to provide an unparalleled engineering tool This program continues to be designed by practicing ventilation engineers Credit for many of the new features goes to the hundreds of users in the mining and tunneling industries throughout the world The applicability of VnetPC Pro to subsurface ventilation system design ranges from the initial concept through the system operations phase of a proje
45. P DROP DOWN MENU cccccsccsccssccucccsccenccescenccesscesseuccesscusseucsesseusseucsesseusseccesseuseensees 34 FIGURE 24 GRID SPACING DIALOG DO dad 36 FIGURE 25 NEW JUNCTION NUMBER DIALOG BOX na 36 FIGURE 26 DXF IMPORT LAYER ELECO ON cod 37 PIGURE 27 COLOR RANGE DIALOG BOX soaiccceivescesonlerizsunvones suntedycadecnaddovei raaa e a raa 38 FIGURE 28 BRANCH CODES DIALOG BOX ni id 39 FIGURE 29 PERSPECTIVE VIE ieee ie te i ERROR BOOKMARK NOT DEFINED FIGURE 30 ORTHOGRAPHIC VIEW ccccscccsccsssccsccusccncccsccuccenccesceuscenccusceuscenseues ERROR BOOKMARK NOT DEFINED FIGURE 3 HAN DATA DAOC BOX cack o Gates 40 PIGURE 322 FAN CURVED IAL OGD OX sessicirantconccoesa o coi 41 FIGURE 33 PAN CURVE GRAPHIC DIALOG DO ie ee ee A EE 42 PIGURE SA FAN IENPU DV Wea ecos 42 PIGURE 395 FAN RES UTS A ES E E suas ooo 43 FIGURE 36 OFF FAN CURVE STATUS WARNING DIALOG BOX ccooccnnccnnocnnoconuncnnoconoronnncnnoconaronnncnnoronarcnnncnnnccnnccnniconos 43 PIGURE EINEN DAN CURVE PEE o O o Udo 44 PIGURE oS PAN RILE MANAGER area ari ectaosntest 44 PIGURE 39 V ED PAN ADS TMEN Ti a A a sce assatene 45 FIGURE 40 FIXED QUANTITIES VEW cr arne E A AS A E A anteoreiens 47 FIGURE 41 ADD FAN OR FIXED QUANTITY DIALOG BOX cssccccsscccseccescccnsceenscceseceeeescseuscseeceeeseeeusceensceeeesenes 48 FIGURE 42 FIXED QUANTITY RESISTANCE seoir E E EE EA A 49 FIGURE 49 FIXED QUANTITY BOOSTER EAN seanna a a a a a a a a Os Ratu an a 49 FIGURE 44
46. PPENDIX A TOOLS AND TOOL BUTTONS ccccccccssscsccsssssccsccsccsssesccossssccscesccsssescessesscssessccsssesccccesees 97 APPENDIX B QUICK REFERENCE AND GLOSSARY cscccccssscccsssscccsssccccssscccsssscccssscccessscossess 102 Ge SOUICK Were RENE ta tas 102 7 1 1 Back round ICO A EE 102 72 Kirchhof s LAWS ar eae a eer Aa 103 7 1 3 Units and CONVE AAAA 103 7 1 4 SEA ONS a sash sseaed Yaa aha cca A aa i Raw ca a A Pa a eo 104 7 1 5 R E TACO S AAA savas nen alah A A A E TAEA 105 7 1 5 1 Resistance perl ensth tor Lalo tes dose ara E E E ETE E 105 R2 Resistance per Length tor Intake Gate Road Snina A EA 105 7 1 5 3 Resistance per Length tor Lons wall Facelis tad 106 7 1 6 EC VOC TU A o tania E E eateataet 106 7 1 7 Data Preparation fOr Modena is 107 7 1 8 Importing trom Old Vineth Files seasca cin 107 7 1 9 General Guidelines for CAD Developed Networks ooooooooooncccccconononnnonononononanononnnnnnnnnnnnnnnnnnnnnonos 108 PEIO Pinior a SM SS VIEW E 108 7 1 11 Possible Deston Entena prado id 109 REESE ExampleDesi n Cote tlancat tas ii Ei eo ata a cea leales 109 TZ ssueeested Maximan AOW Velar tl a 110 tez GROSSAR YOR TERMS io ii O Iori cids 111 So AFPENDIX C INDEX 000 iaa AA AAA Aa 114 List of Figures FIGURE RENEW MODF E CREATION bas fac oes e denen e O 11 FIGURE 2 NET SELECTION DIALOG BO da nd asias re een aks 11 FIGURE 3 MODEL INFORMATION VIEW Isra id 14 FIGURE AF BRANCHGINPUT VE Wo li 16 FIG
47. URE 5 BRANCH INFORMATION DIALOG BOX cc cece cceeccscccesccesccecceusccusccecceusceescceucceusceesccecseusccusceeseeusceuceeees 17 FIGURE 6 FRICTION FACTOR DIALOG BOX ii 19 FIGURE 7 RESISTANCE PER LENGTH VALUES DIALOG BOX ooccoccncconocnnccnoconocnnconaconocnnccnoronoconccnaronocnnconaronocnnroniconicos 20 FIGURE 8 AUTOMATIC BRANCH LENGTH DIALOG BOX occ cece cecccecceeccccceccusceucccsccesceccesscussecsesceuscencceeseuscensees 21 FIGURES RECTANGLE PROFILE TYPE a 22 PIGURE IO C RCELEPROFME TYPE SS 23 FIGURE II ARCHED PROFILE F YPE naapa aa 24 FIGURE 12 SHOCK LOSS FACTOR DIALOG BOX srin tiine ioa a E E id 25 FIGURE 137 BXAMPEE AIRWAY dsd 26 FIGURE 142 EDIT JUNCTION DIALOG BOX tdi aiii 27 FIGURE 15 CREATE FAN DIALOG BOX rn iii 28 FIGURE 16 BRANCH CONTAMINANTS DIALOG BOX occnoccnnccnnnoconoconanonnncnnaronancnnoconaronnncnnoronaronnncnnaronaronnncnnnrcnaronancnnns 29 FIGURE 7 ADD LABEL DIALOG BOX cias 29 FIGURE 15 SELECTED BRANCH LAS Ear id 31 FIGURE 19 BRANCH GROUPS DIALOG BOX 0 ccsccssccssccssccssccvcccsccssccvcccscesscevcccscessceececscesscevscessesscesccescesscesseesees 32 FIGURE 20 3D VIEW OF A METAL MINE WITH 3D SPIN TOOL ACTIVE cccccccccsccceccecccccsccesccscesccuscescesseussensees 33 FIGURE 21 CROSS SECTION VIEW OF A METAL MINE ccccceccseccsccceccesseucccuccusceuscenscusseucsesscusseucsesseussenceesseuseensees 33 FIGURE 22 BACKGROUND COLORS DIALOG BOX ia ido 34 FIGURE 23 ACTIVE GROU
48. VnetPC Pro USER S MANUAL amp TUTORIAL Mine Ventilation Services Inc 1625 Shaw Ave Suite 103 Clovis CA 93611 USA Telephone 1 559 452 0182 Facsimile 1 559 452 0184 Email support mvsengineering com Website www mvsengineering com 1 Ze Table of Contents INTRODUCTION II cs 7 OVERVIEN OEVNETEC cuina dia it 8 2 YNETEC TTS APPLICATIONS AND USES croel ae au ee 8 22 gt BACKGROUND THEORY OE VNETPC cecilia acute ON OSUNA 8 23 LASDOF VIAIN PROGRAM FEATURES o ae 8 2 4 MINIMUM SYSTEM REQUIREMENTS OF NET as 9 20 SOFTWARE ENCRYPTION a ios 9 205 SETUP PROCEDURE asta oboe 10 DATA PREPARA TION AND INPU E ii a 12 Sl VENTLATON NETWORK SCHEMATIC ados 13 3 1 1 A O A A E N ES 13 3 12 as A A A A A 13 3 1 3 Sehe mate La yolan a a E dua 13 Note Scaling and Offset of Coordinates during DXF impott ooooooonnnnnnncnncncncnnnononononnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnonnnnonnnnns 13 I2 DESC DATA a a sacs Sates 14 3 2 1 Fle NaMe eric Sate E A A en ca ceil clare ias aah 14 3 2 2 Units and Conversi n DU ida 15 3 2 3 POWER CO ile 15 3 2 4 Air Density and Regulator Sizing and Shock Loss Calculator oooooooonnncnncnnnnnnnncnnnononnnnanannnnnnnos 15 323 Notepad COmMent ida 15 J BRANCH DATA o cio es 15 Jl Branch Data Formats eesin A E a Ei 15 3 3 1 1 Resistance olle eee 17 Si Pressure Drop and Quantity Dita oris SA ads 18 3 3 1 3 Atkinson Frichon Factor kL Li AAA A AAA AA AA Eos 18 3 3 1 4 Resistance p
49. a particular cell the user can press either the Enter key or the Tab key to progress to the next cell This section allows the user to enter any and all of the branch 25 parameters and or descriptions about each branch that are needed for model development The columns in all tabular views may be frozen hidden or shown using tools under the View menu Figure 4 shown previously displays an example of the Branch Input view In the Branch Input view the Find option may be used under the Edit menu or via the Find Branch icon binoculars on the tool bar These tools are different The Find option seeks up or down a selected column for an input text string The Find Branch option allows branches to be located either by entering from and to junction numbers or by finding the next occurrence of a particular junction number The Go To Branch tool will locate a branch based on its unique Branch ID This is useful because branches may not always be sorted in order of Branch ID The Replace option allows the user to make single column or global changes to the input data 3 3 3 Schematic View VnetPC Pro features a reversal function which signals when airflow in a particular airway has changed direction from that which was intended In order for this function to work properly the user must define each branch with junctions set up in the proper order similar to fans and fixed quantities Once a simulation is executed reversed airways will be tagged as
50. ablish a ventilation Schematic in AutoCAD and create a new VnetPC file from the data The step by step process provides the user with an in depth look at how to get started 5 2 Setting Up the Model in AutoCAD Ventilation Schematics for underground mines can be developed by overlaying a branch network onto the mine plan using AutoCAD saving as a DXF file and importing the file into VnetPC The following subsections describe this process 70 5 2 1 Adding the Ventilation Layers The first step is for the user to create layers using the Layer Properties Manager in AutoCAD It is suggested that for each section component of the mine a new layer be created for the network Schematic e g set up new layers for each level ramp shaft etc An example Layer Properties Manager dialog box has been copied out of AutoCAD and is shown in Figure 66 to demonstrate this feature The original drawing layers are 1400 1600 1800 1920 and 2000 The layers 1400VENT 1600VENT 1800VENT 1920VENT and 2000VENT were created for the purpose of importing a Schematic into the VnetPC program x ho Current layer 1400WENT Search for layer Q ES BK SP L Color Linetype Linewe Plot 5 o Ew Continu Defa Color or Ew Continu Defa Color Continu Defa Continu Defa Color Continu Defa Color_5 w Continu Defa Color Continu Defa Color_5 Continu efa Color Continu Defa
51. ad Ventilation Volumetric Efficiency The distance as measured around the outside edge of an airway perpendicular to the direction of airflow The practical unit or PU is defined by k L P 52 A 3 It is the imperial equivalent of the Ns 2 m 8 unit of resistance An internal vertical or inclined airway used to ventilate between levels A large vertical or inclined airway used for ventilation and or materials men haulage Losses in kinetic energy of air due to obstructions in an airway A condition encountered by a fan usually associated with a sharp drop in airflow increase in pressure and excessive cavitation at fan blades that can cause serious vibration and structural damage This occurs when a fan is operating above its characteristic curve A wall constructed usually of metal or wood to stop airflow in an airway Generally more permanent than a brattice A key component of a mining system is bringing sufficient air into the mine and then distributing it through the workings in an adequate quantity to support both workers and equipment A unit of measure to identify the general efficiency of a ventilation system It is defined as the sum of all air usefully employed in the ventilation system divided by the total amount of air provided by the main fans 113 8 Appendix C Index 3D perspective 34 3D spin tool 26 add fan 41 air density 14 Atkinson friction factor 17 Atkinson s equation 17 automatic
52. alize Quantity Quantity kcfm Figure 83 Importing the DXF File into VnetPC Once the user selects the Import DXF tool a standard Open file dialog box will appear prompting the user to identify the DXF file to be imported The user then selects the DXF file The Layer Selection dialog box shown in Figure 86 will then appear prompting the user to identify the layer to be imported In this case the 1400 Level 1600 Level 1800 Level 1920 Level and 2000 Level layers will be imported The layers can only be imported one at a time At this point the user may select the default branch type to be R P Q k Factor or R L The units drop down menu is utilized when the DXF file and VnetPC model have different units 83 Layer Selection Layer Name Default Branch Type A Uruts Imperial Figure 84 Layer Selection Dialog Box As the layers are imported the schematic Figure 87 will begin to appear on the screen If the schematic does not begin to appear select All from the Zoom menu or the Zoom All button on the Toolbar This will show the extents of the schematic on the screen If a junction 1s connected to more than one branch the junction will be illustrated with a circle If the junction is connected to a single branch the junction will be represented with a triangle as illustrated in Figure 87 Figure 85 Plan View of Imported Schematic Initially the schematic may seem complex however each no
53. an curve based on series parallel fan theory The series and parallel fan data are shown in columns in the Fan Input and Fan Results views see Figure 34 and Figure 35 File GoTo Edit View Fan Tools Window Help Oe S Oc SRl AdxbK B Hey Wet 0 User Manual wdb Fan Input A Fi o 7 esis ae ARO aa ves SRA Tos 000 ves For Help press Fl MO Figure 32 Input View 42 2 VnetPC Pro VnetPC PRO User Manual vdb Encima File GoTo Edit View Fan Tools Window Help Dah S dhK e we VnetPC PRO User Manual vdb Fan Results Fan Fan Operating Curve Fans in Fans in aon Pressure Quantity Rall Cost Status Parallel rae Description Branch ID Power Fan Status in w g kcfm hp Syr hp Off 19 23 18 76 7545 Off E N A 155 68 203 49 81832 On 105 313 06 For Help press Fl NUM Figure 33 Fan Results View After execution of the ventilation model a warning message dialog box will appear 1f one or more fans are operating off their fan curves see Figure 36 The dialog box 1s a warning and does not affect the execution of the simulation One or more fans are off curve status Figure 34 Off Fan Curve Status Warning Dialog Box Fixed pressure fans are useful when modeling a known fan at a specific operating pressure or when modeling natural ventilation pressure NVP In the case of a fixed pressure fan the fan curve should not be defined in the Fan Curve dialog box only
54. an existing Branch Template to the selected branch Make Template allows the user to make a Branch Template from the selected branch This will create a Branch Template using all possible Template fields of that branch and will not allow the user to select specific fields A Select Template dialog box will appear as shown in Figure 47 Select Template Cancel Template Name Description E oo Rane Figure 45 Select Template Dialog Box The desired template can be selected and applied by clicking on the appropriate row and selecting OK If multiple branches are selected a dialog box will appear asking for the template application to be confirmed This will prevent accidental modification of large branch selections 52 Branch Templates can be used to modify the group assignments of single or multiple branches in additional to most other branch parameters Surface state shock loss and other unique properties cannot be altered via Branch Templates Length values will not be applied unless the Auto Length field is disabled and the recipient branches already have Auto Length disabled Airway Profile must be selected if any corresponding fields are selected such as diameter height width etc The input data types Resistance R Atkinson Friction Factor k Factor and Resistance per Length R L can be used as estimates predictions of actual or future mine conditions Pressure Quantity p Q data cannot be used in esti
55. anch fan and descriptive data for the network have been fully entered When the program has finished execution each view and any previously accessed windows will be updated with the current information Execution may also be initiated by hitting the Execute Simulation tool button denoted by a calculator symbol on the toolbar in any view The contaminant simulation must be executed separately and directly after the airflow 54 simulation has been accomplished If the user changes the model in any way after executing the airflow simulation the user must execute the airflow simulation again before the contaminant simulation may be executed Unlike the previous versions of VnetPC relative pressure analyses are conducted during every execution of the code the user does not have to tag on or off Relative pressure is the difference in pressure from each node to the user specified reference junction The user may specify the reference junction in Model Information view This reference is often useful to determine relative pressure difference between two unconnected junctions Output of the relative pressure is viewed on the Schematic in square brackets or in the Junction Data view The user can select whether to view or hide the relative pressure data on the Schematic by selecting Preferences gt Relative Pressure 4 4 Viewing the Results of a Simulation Once the program has been executed the results of a simulation may be vie
56. ariation in cross sectional area or any other configuration that causes a change in the general direction of airflow Users may select Reference for additional information for selecting a Shock Loss Factor After users enter a shock 24 loss factor and press OK the calculated shock loss resistance will appear in the Branch Data dialog box Shock Loss Factor Shock Loss Factor ll 0 20 Cancel Reference Figure 12 Shock Loss Factor Dialog Box 3 3 1 8 Parallel Branch Tool A tool is available to allow the user to rapidly adjust the resistance of a branch according to parallel network theory This tool is accessible in both the Branch Input view Parallel Factor column and the Schematic view Branch Data dialog box gt Parallel Factor The user may enter a number with the default being 1 If the user selects a 2 then the code will adjust the input branch resistance to double the number of airways represented by the branch If the user were to enter 0 5 then the resistance would be adjusted to give half the number of airways represented in the branch If the user enters 1 then the resistance is reset to the original value During ventilation surveys resistances are determined for parallel entries and are input directly to the model Although only one branch is modeled it will sometimes actually represent two or more parallel entries Care should be taken to identify exactly how many entries are incorporated into t
57. ct Given information that describes the geometry of a ventilation network airway resistances or dimensions and the locations and characteristic curves of fans the code will produce listings of many ventilation parameters The output includes predicted airflows frictional pressure drops air power losses in airways contaminant flows and concentrations and fan operating points VnetPC Pro has been developed specifically for computers operating under the Windows environment The system is supplied on one USB Flash Drive Data files and fan databases prepared using the previous version of VnetPC 2007 and VnetPC 2003 can be imported and converted for use with the latest program Prior to installing the software it 1s recommended that the user become familiar with this User s Manual This manual provides an overview of the VnetPC Pro package and software encryption routine that 1s recommended for both new users and for users of previous versions A tutorial section is included with this manual which provides a quick start to developing ventilation networks Comprehensive Help menus are included with the program to further assist users in understanding how the program works To access the Help menu click on Help above the tool bar If you have any questions or comments regarding VnetPC please do not hesitate to contact us Mine Ventilation Services Inc MVS maintains a comprehensive web site which includes up to date information on Vn
58. cument 80 E VnetPC Pro File View Help For Help press Fl MODIFIED Figure 80 VnetPC New Model Dialog Box In this case the user will choose a VnetPC Pro File Then another dialog box will appear prompting the user to select units as shown in Figure 83 For the Tutorial the user will select Imperial Units 2 VinetPC Pro File View Help CD 7 Select Units E Please select the system of units for the document Imperial SI a For Help press Fl Figure 81 Select Units Dialog Box 81 A blank model will appear with the Model Information view In the Model Information view the user provides general data for the model as shown in Figure 84 C VnetPC Pro Untitled File GoTo Edit View Tools Window Help D Hs sw Untitled Model Information Model Data Title Avg Fan Efficiency 65 2 Cost of Power 0 04 EM hr Reference Junction 7 Avg AirDensity 0 075 Ib Units Imperial Comments Data Summary Branches O Fars Junchons O Fired Quantities Last Execution of Simulation Date H A Iterations Time H A Errors Modified Since For Help press Fl Figure 82 Model Information View The model title and any particular description can be entered to further identify the purpose of the simulation The unit basis is selected as either Imperial or SI and can be changed from this view The user can also enter the average power cost and fan efficiency in this vi
59. d A single file is used for the network input schematic coordinates and contaminant data A separate archive file is used to store multiple fan curves Creating importing editing or viewing fan curves are performed within the VnetPC program The VnetPC program comprises ten screens for the input and display of program data The screens are listed on the Menu Bar under the Go To menu These views are Model Information Branch Input Branch Results Fixed Quantities Branch Template Fan Input Fan Results Junction Data Schematic Contaminants This section details the content and form of the input data required for the VnetPC program The data requirements are presented in eight categories 1 Ventilation Network page 13 2 Descriptive Data page 14 3 Branch Data page 15 4 Fan Data page 39 5 Fixed Quantity Tool page 47 6 Contaminant Distribution Data page 50 7 Branch Template page 51 8 Transient Time Calculator page 53 12 3 1 Ventilation Network Schematic A ventilation network is a graphical representation of a ventilation system that consists of a set of junctions and interconnecting lines branches which represent air courses in the underground facility The following subsections describe the schematic requirements 3 1 1 Closed Circuit The network schematic must consist of interconnected branches that form closed circuits Each branch should represent a single airway a group of airways or lea
60. dd Branch tool or similar The zoom in out tool is also enabled by scrolling the center wheel on the mouse The zoom tool can be used in all four model views plan view cross section long section and isometric The Eraser Tool allows the user to rapidly remove unwanted objects from the schematic The tool will work with branches nodes and text A detailed Undo Redo option ensures that erased data may be recalled in the event of a mistake Single or multiple objects may also be deleted when selected by hitting the delete button or selecting deleted when right clicking with the selection tool A confirmation dialog will appear if multiple objects are selected to prevent accidental deletions The eraser tool can be used in all four model views plan view cross section long section and isometric The Edit Tool allows the attributes of existing objects to be amended The user must select the required node branch or text to obtain the properties of the object The edit tool can be used in all four model views plan view cross section long section and isometric The 3D Spin Tool allows the schematic to be rotated in isometric view To rotate the user must click and hold the left mouse button while dragging the cursor across the screen The user may left click anywhere in the schematic view to rotate the model The 3D spin tool can only be used in isometric view 3 3 4 Branch Selection and Editing Previous versions of VnetPC
61. de can be moved after the import process is complete Furthermore the layers or groups can be hidden from view to simplify the 84 screen data Once all of the layers have been successfully imported into the program their general group attributes need to be defined When branches are imported into the program the junction numbers are automatically defined This numbering is conducted sequentially and progresses from right to left across the network in Plan View 5 3 2 2 Defining Group Attributes Each layer or group has a set of general attributes which separate it from the other groups In this case each group represents an individual level having a discrete range of elevations For example a group labeled 3000 Level may have a range of elevations from 2950 to 3050 which separates it from the others groups Any changes to a group s attributes may be made by clicking on the Groups item on the Tools menu shown on Figure 88 Branch Groups Groupe Default Z Coordinate ft Group Group Number Name ajose A a sheo ooo Show All s ES em e S 2000tever 200 Hide MES Add Group Delete Group SetActive Figure 86 Branch Groups Dialog Box The Branch Groups dialog box will appear which allows the user to select the group to be modified from the list provided In this case one may choose to modify the attributes of the group 2000 Level To modify this group select any of the group attrib
62. dit Fixed Q or Delete Fixed Q respectively The Fixed Quantity tool is applied in the Schematic view by selecting the Fan or Fixed Q icon el or by selecting Tools gt Fan or Fixed Q The user must then select Fixed Quantity when prompted as shown in Figure 41 UY VnetPC Pro VnetPC PRO User Manual vdb Fixed Quantities o lO misa vee File GoTo Edit View FixedQ Tools Window Help Dx Dal amp gt lp ac Fixed Q Fixed Booster Branch Regulator Total Orifice Operating No Branch ID From Quantity Pressure Resistance Resistance Resistance Area Cost Description FixedQ ID kcfm in w g P U P U P U fe Syr i 1 095 0 36677 NUM Figure 38 Fixed Quantities View 47 Add Fan or Fixed Quantity Select ltem to Add Fired Quantity Cancel Figure 39 Add Fan or Fixed Quantity dialog box The Fixed Quantities view will automatically be updated according to the information entered in the Branch Input or Schematic views The input data type R p Q k factor R L dictates the resistance of the branch It should be noted that negative integers cannot be entered and it is necessary to swap the branch node numbers if airflow is to be reversed This resistance is usually the natural resistance of the airway without a regulator or fan Upon execution the program calculates the regulator resistance and orifice area or the pressure of the booster fan required to achieve the specified air
63. e Recre Black seme Bright Green Sample 8 Unused Back Sampk Set s Default Default branch code shown in bold text To reorder rows select a row and drag it up or down Figure 28 Branch Codes Dialog Box 3 3 4 8 Ventilation Structure Symbols Ventilation structure symbols are entered in either the Schematic or Branch Input views From the Schematic view the user enters a symbol in the Branch Data dialog box and in the Branch Input view the user selects from a list of six symbols These symbols can be used as desired however they are typically used to denote the following D single door DD double door airlock S1 single stopping bulkhead S2 double stopping bulkhead B Brattice R Regulator These symbols can be toggled on off by tagging Symbols under the Preferences menu 3 4 Fan Data The user may add fans in the Branch Input Fan Input or the Schematic views When a fan or fixed quantity of air is added to a branch an F or a Q will appear in the FQi fan fixed quantity inject reject column in the Branch Input view The Fan Input view will be updated to incorporate the new fan details It is important that the user input the junction numbers in the expected direction of airflow for fixed quantity or fan branches In the Branch Input view a fan is added by selecting the fan input icon or double clicking the cell under the FQ1 column In the Fan Input view the user may add a fa
64. e Create Branch icon on the Toolbar To add a branch click on the branch origin from node then holding the left mouse button down 87 move the mouse to the branch termination point similar in operation to drag and drop features of other Windows based programs A segment of the exhaust shaft is being inserted in Figure 91 If there 1s an existing node in close proximity to either of the two nodes From To then the branch will automatically snap to those junctions From To nodes may also be changed in Branch Data dialog by editing the From To junction entries If the user chooses to either begin or terminate a branch by intersecting an existing branch then the existing branch will be split and a junction inserted Branches can be added deleted or split in Plan Cross Section or Long Section views Figure 89 Drawing Branches in Schematic Cross Section During the initial schematic development in AutoCAD a node was inadvertently left out On the 1800 level top level the location for the regulator at the intersection of the level and the exhaust shaft was omitted This can be corrected by either adding a branch for the regulator or by inserting a node in the existing branch Adding a node would split the existing branch to allow for the addition of the regulator To do this the 1800 level must be displayed on the screen see Figure 92 To view the 1800 level the user selects the level from the list provided by the drop d
65. e Ventilation Services Inc does not make any representations as to the correctness of the provided resistance data This data should be used only for initial planning purposes and every effort should be made to accurately measure the actual friction factors and resistances encountered at the mine 7 1 6 Velocity Limitations Particular attention should be paid to the velocity of the air as it travels through each airway Excess velocities can actually reduce the effectiveness of the ventilation system by liberating larger quantities dust and can result in very high operating costs The following table shows some recommended maximum velocities for various airways in mines 106 Airway Description m s ft min Working Faces 4 0 790 0 Conveyor Drifts 5 0 985 0 Main Haulage Routes 6 0 1180 0 Smooth Lined Main Airways 8 0 1575 0 Hoisting Shafts 10 0 1970 0 Ventilation Shafts 20 0 3940 0 It should be noted that along with maximum air velocity considerations there are minimum air velocities dictated by various governing bodies One such limit is that a minimum air velocity of 0 3 m s or 60 ft min be maintained throughout the mine 7 1 7 Data Preparation for Modeling When modeling a mine ventilation system It 1s always best to start from measured resistance data This data can be obtained by conducting either a full or partial ventilation survey If current measured resistance data is not available then empirical data obtained from one of many v
66. e color may also be changed in the Define Colors menu by selecting Junctions The user may also select to define colors for the Branch Code as opposed to a parameter range This allows colors to be assigned for different types of branches which can be specified from certain categories during entry of the input data The basic branch types available are Default Intake Neutral Return Active and several user defined branch labels Within the Preferences menu the user can select whether to use branch colors based on parameter range branch code or whether to disable the color option entirely 6l Junction Range This command allows the user to display a selected series of nodes This is particularly helpful when sections of the Schematic are no longer in use and the user wishes to show only relevant areas The total junction range is from to 10000 Letter Size This command allows the user to adjust the size of text shown in the Schematic view and when plotted It is often useful to customize the lettering size so that the labels are easier to read The range of font sizes is as follows screen 4 to 12 point printer 4 to 14 point and DXF 1 to 200 These fonts are actual sizes and do not vary according to coordinate range Plot Labels This command allows the user to print with either a title block and or a legend with the Schematic The plot labels will only be displayed in Print Preview or when the user decides to print The user can
67. e pitch This term defines the amount of wasted energy used to achieve the desired airflow exerted by a fan A fan that is 80 efficient is applying only 80 of the total work to the air and wasting the remaining 20 This term is generally applied to ventilation systems operating under an induced positive pressure This has the effect of pressurizing air in gob areas A junction is a point where branches meet The VnetPC Pro program adheres to Kirchhoff s Laws regarding junctions The standard of airflow measure in the imperial basis of units Thousand cubic feet per minute The Atkinson friction factor describes the airway roughness It is a function of air density and is computed as the product of the Chezy Darcy coefficient of friction and the air density divided by a factor of 2 The unit of pressure used to calculate airway resistance in the VnetPC Pro program It is not practical to measure differential pressures below 1 milli inch water gauge 1 milli inch 0 001 inch W g The series of branches that make up a ventilation model is referred to as a network The ventilating pressure induced by the heating or cooling of air as it circulates through mine workings This can be a significant factor however it is heavily dependent upon outside atmospheric conditions The annual cost of running a fan or ventilating an airway 112 Perimeter Practical Unit Raise Shaft Shock loss Stall Stopping Bulkhe
68. e values will be imported as 20 0 and 20 1 Snapping coordinate values has the advantage of producing a clean schematic even if it is digitized directly on the screen using the system mouse 7 1 9 General Guidelines for CAD Developed Networks The use of AutoCAD or other mine planning software to develop the ventilation model is an important and powerful tool included in the VnetPC Pro program In order to successfully use this tool certain guidelines should be kept in mind e All lines drawn in the graphics program need to be joined meaning that one line begins where another ends not just close to it unless the open end represents a portal or top of a shaft e When drawing airways in AutoCAD overlaying a mine map it is important to ensure that the airways are drawn on their own layer separate of the mine map e When using mine planning software the center line layer is often useful for model generation e Try to keep networks simple and limit the amount of branches in the network to minimize the possibility for errors and omissions This may require the use of filters to reduce the number of line segments particularly when curved entries are encountered The model will not initially be ready for execution All branches require that a resistance be assigned to them Do not forget to identify the in atmosphere surface branches 7 1 10 Printing a Single View A single view can be individually printed by selecting the Print Active View o
69. ect OK to incorporate the curve into the model or Save to export the curve to an external fan curve data base Note that the fan curves are unit dependent and that the curves are converted if the unit conversion utility is used Fan Curve Fan Curve Description Name Fan 1 Setting 5 Comments Fan Configuration Fans in Parallel 1 Fans in Seres Fan Adjustment Original Actual Air Density lb ft 1 2 12 Frequency 60 60 Adjusted Fan Curve Points Motor Input Point Quantity Pressure Efficiency sin Ter No kc im Cin w q 55 hp i a mo eoo o IE 2 wo s00 s wo 3 soo wooo e e a ooo roo soo mz 7 Figure 30 Fan Curve Dialog Box Cancel Remove Import Save Using the entered fan characteristic curve VnetPC Pro will generate a graphical display as shown in Figure 33 After the simulation is executed the predicted operating point with motor input power is plotted 41 Fan Curve Description Graphics Name Fan P in w g MIP hp Lancel Setting 5 20 300 Remove Fan Configuration Fane in Parallel 1 Fans in Seres 7 Fan Adjustment Original Actual Air Density lb ft 1 2 1 2 Frequency 60 60 50 100 Q kcfm Pressure Curve Input Fan Power Points Figure 31 Fan Curve Graphic Dialog Box The user is also allowed to input data for multiple fans series or parallel When multiple fans are selected the program will develop an equivalent f
70. entilation texts may be used The data required to model a ventilation system with the VnetPC for Windows program includes 1 A schematic representation of the ventilation system The schematic consists of junctions also referred to as nodes and delineating branches The network schematic must represent a closed circuit of interconnected branches Each branch should represent a single airway a group of airways or leakage paths that can be combined into a single equivalent path It is important to remember to identify all portals and surface connections as in atmosphere by checking the appropriate box By identifying them as a surface opening the program will automatically connect them to a common atmospheric node 2 Numerical data used to define each branch of the system Branch resistance data may be entered in any combination of four forms Each branch entry requires respective junction numbers to be entered under from and to headings 3 Data defining the location and characteristics of each fan or fixed quantity in the system The fan data required consists of a fan location flow direction fan type fixed pressure or with characteristic curves and an initial estimated operating point A fan may be located in any branch that does not have a fixed quantity associated with it The order in which the junction numbers are entered defines the direction of the fan 4 Descriptive data for both user preferences and model documentation It is
71. enu then click on the branch where the fan will be located Once the branch is selected the Add Fan or Fixed Quantity dialog box will be displayed as shown in Figure 99 In this dialog box either the fan option or the fixed quantity option can be selected Add Fan or Fixed Quantity Select ltem to Add Fired Quantity Cancel Figure 97 Fan or Fixed Quantity Dialog Box If the fan option is selected the Fan Data dialog box Figure 100 will be displayed This dialog box allows the user to input the fan characteristics to the model Note that the nodes From To order will specify the airflow direction for the fixed quantity or fan 93 Fan Data Fan Input Data From 43 Pressure 0 Description Fan Curve Statys E Off Fans in Parallel 1 Fans in Series 1 Last Results Pressure M A ir Motor Input Power NA Quantity NAA cfm Air Power M A Curve Status MA Operating Cost Heb Figure 98 Fan Data Dialog Box Another tool included in VnetPC allows the user to create a single fan and apply it to the model as a multiple series or parallel installation This tool will automatically adjust the fan curves for multi fan installations with identical fans If a fan is already defined in the fan database or if a fan characteristic curve is going to be added to the model then the user selects the Edit Curve icon This will bring up the Fan Curve dialog box that contains the fan curve data series as illustrated in
72. ept that the device driver selected in the Print Setup will be a system plotter VnetPC allows plotting to a complete range of plotters supported by Windows Providing that the plotter device driver has been loaded in the Windows Setup VnetPC should recognize and communicate with any plotter 4 4 9 DXF File Generation The user can export the Schematic to a DXF file This feature is accessed through the Schematic view using the Tools DXF file menu A dialog box will appear for the user to Save As in DXF format then another dialog box will appear prompting the user to select a parameter to export illustrated on Figure 59 This feature allows the users to define which parameter or no parameters to be exported The exported DXF file layers will be named automatically to allow the user to easily recognize what data is contained on each layer DXF Select Information Select Parameter to pass Hone Show node numbers Figure 57 DXF Select Information Dialog Box 4 5 Changing the Appearance of a Table View The display and arrangement of columns in table views can be customized by the user The columns and rows can be rearranged widened or narrowed removed or added The columns can be easily rearranged by clicking on the column or row header with the left mouse button to hi light it then by clicking and dragging it to its new position The column width can be changed by clicking on the column separators in the column header and draggin
73. er Lensi Data Format estic read 19 Z315 Automatic Tenet POON l ranie a 20 3 3 1 6 Auto Calculate Arca Perimeter Tool a E EE 22 3 3 1 7 Shock Loss Calculator ics eit cess A A AA E A EO TE 24 3 3 1 8 Parallel Brano Tools A A A E 25 3 32 Branc t Input Vie W arn nan EEE A nin wenees Auch ae nictiasteseacaa ate tme sees dusaty tanta date 25 RAA PVC Me TALI ON r N EA A AEE 26 3 3 4 Branch Se lec MON and lt CMAN GS crases aA A E NE EEN 30 3 3 4 1 Level and PErspEeC IVE onnaa A IA E E E EA AN AAA de 31 3 3 4 2 Grias and SaPA d a e tio ld leo caer 35 3 3 4 3 Tanco Crea Onsa ea T E A A E E dosdaw tees 36 3 3 4 4 Importing DXF Files from CAD and Mine Planning ProgramS cccccccccccnnnononononnnnnnnnnnnnnonnnnnnnononnnnannnnnnnnnnnos 36 3 3 4 5 E E eA eee se A EAO IATA ENAA ESA AAAA ANA IAE Veale teenie A 37 3 3 4 6 Excluding Inactive Dranches nara E E E ios 38 3 3 4 7 E A a a a a een raT Renae rte earner Neen a eae 38 3 3 4 8 Ventilation Siucture Symbols sd AE ASAS AAA AA es 39 It BAN DATA docto 39 3 4 1 Pan Escalion and Elo WD COM a 39 3 4 2 Fn Lype eeso a A E A bain aadaRnceecmuas 40 3 4 3 Pan Pie Manor ari E N 43 3 4 3 1 Creaune a TanyC uty Data BAGG a n a elle tbc 45 3 4 3 2 Importine a tan curve mo a mode acia A Sitges Laem ait vac ceadaveesie 46 3 4 3 3 Saving a fan curve from a model into the Fan Curve Data Base oocccccncccccccnononononnnnnnnnnnonnnnnnnononononananonos 47 3 4 3 4 Importing fan curves created in DuctSIM to VnetPC Pr
74. etPC We also offer free technical support to all users of the latest version of the VnetPC program Thank you for choosing the VnetPC software program and for supporting the continued development of the code Mine Ventilation Services Inc 1625 Shaw Ave Suite 103 Clovis California 93611 United States of America Telephone 1 559 452 0182 Facsimile 1 559 452 0184 Email support mvsengineering com Website www mvsengineering com 2 Overview of VnetPC The VnetPC program is designed to assist the mine ventilation practitioner in the planning and monitoring of underground ventilation layouts Given data that describes the geometry of the mine network airway resistances or dimensions and the location and characteristic curves of fans the program will provide graphical and tabular representations of various predicted ventilation parameters 2 1 VnetPC Its Applications and Uses VnetPC can simulate existing ventilation networks such that fan operating points airflow quantities and frictional pressure drops approximate those of the actual system This is accomplished using data from ventilation surveys together with information determined from known airway dimensions and characteristics Proposed subsurface facilities may also be designed using VnetPC Such simulations are conducted by incorporating physical input data from conceptual plans with documented design parameters used to determine estimated resistances for airways in the ne
75. etected by the program will be listed in a dialog box on the screen Information regarding these errors can be found in Section 3 4 1 and the Help program 96 6 Appendix A Tools and Tool Buttons The following list is a description of the buttons and tools available in VnetPC Pro The Schematic view has the following buttons and tools Es Selection Pointer du Create Junction i Create Branch ce Fan or Fixed Q og Contaminant A Create Label Sl Zoom a Erase Fa Edit Information 97 This button selects branches and is the default mode The user can drag and drop existing junctions using this tool It also has right button mouse features for editing objects This tool creates inserts a junction This tool creates a new branch This tool features a drag and drop approach Select the initial point and drag to the second point keeping the left mouse button depressed This tool creates a fan or fixed quantity and inserts it in the selected branch This branch adds a contaminant to the selected branch This tool allows the user to annotate or add text to the schematic This tool allows the user to window or zoom in on a specific area in the schematic The user may zoom to a window by dragging a rectangle on the screen The user may also zoom in and out using the left and right mouse buttons respectively each click will zoom in or out one division This tool allows the user to rapidly erase selected ob
76. etric View 3D the user may rapidly change the active group using the drop down menu as illustrated in Figure 23 Group Filter ie i m m 5 4 000 Leve 2 1400 Level 3 Surface 4 1440 Level 5 6 T 1600 Level 1800 Level 1920 Level Figure 23 Active Group Drop Down Menu Non horizontal airways such as ramps and shafts may be entered in Plan View or in a section view The nodes should already exist when working in a section view the start and end nodes however this is not necessary A branch can be drawn from an existing start node to a new node that 1s not attached to an existing branch In this case the coordinates of the new node will be established by taking the two coordinates shown on the graphical view for that point and transferring the coordinate perpendicular to the graphical view from the start node to the new node 34 For example if a branch is drawn from an existing junction in the cross section view Z X to a new node then the Z and X coordinates of the new node will be determined by the placement of the junction and the Y coordinate will be taken from the start node This only applies for section views since default Group z coordinates will be used for branches created in Plan View Once the junctions have been added they may be moved across the entire vertical extent specified for that level by dragging the nodes within the sectional views
77. ew A reference junction is also selected This junction is usually associated with a surface condition A relative pressure table will be calculated relative to this point The average air density is also entered in this view This density may be estimated based on average mine conditions but it is usually most accurate if several measurements are taken at different points in mine to get an average density This value is defaulted to the mean air density at Sea Level 0 075 lb ft or 1 20138 kg m This value is needed to compute the orifice area for any regulators listed in the Fixed Quantities View This air density is not used anywhere else in the program 5 3 2 Schematic View The Schematic view is obtained by selecting Schematic from the Go To menu 82 5 3 2 1 Importing the Schematic The screen will be blank as no schematic or model has yet been input To bring the network into VnetPC Pro the user should select Tools gt Import DXF see Figure 85 E VnetPC Pro Untitled File GoTo Edit View Preferences Zoom Window Help Dal amp E G Execute Simulation P R ege IS E Execute Contaminants Error List wei Untitled Schematic Comments Unit Conversion Branch Codes Groups Auto Length Transient Time Import DXF DXF File Selection Pointer Create Junction Create Branch Fan or Fixed Q Contaminant Create Label Zoom Eraser Edit Plot Existng Junction 3D Spin Tool Norm
78. fans in the 3D view Fans can only be input in the plan and section views Add Fan or Fixed Quantity Select ltem to Add Far Fixed Quantity Cancel Figure 15 Create Fan Dialog Box The Create Contaminant feature is handled in a similar fashion as the fan tool The create contaminate tool can only be used immediately after the Execute Simulation button is selected and before anything else in the model is edited The create contaminant tool may be used to edit contaminants in consecutive branches after executing the simulation but the moment another tool is used to edit the model the Execute Simulation button must be selected again before another branch contaminant is added or modified After selecting the create contaminant tool a 28 dialog box will appear illustrated in Figure 16 which requires the user to input either a contaminant volume flow or a concentration The input concentration represents the concentration of the emission at that point in the airway The user should not enter the total contaminant concentration which will include any upstream sources The output contaminant flow and concentration evaluated by the program will integrate all of the sources to determine actual concentration and volume based on a steady state condition The user cannot create contaminants in the 3D view Contaminants can only be input in the plan and section views Branch Contaminants ID 8 Fron 10 Desc
79. flow The new resistance or booster pressure is added to the existing resistance data whether the input data type is R p Q k factor R L If the fixed quantity results in increased resistance the new Total Resistance is the combined resistance of the branch input data and the calculated resistance of the fixed quantity If the fixed quantity results in an added booster fan the pressure of the booster fan will reflect the pressure needed to overcome the branch resistance and resistances elsewhere in the model The fixed quantity dialog box displays the most recent results of the model execution under the heading labeled Last Results Figures 39 and 40 show the Last Results for branches with fixed quantities resulting in increased resistances and added fan pressures respectively 48 Fixed Quantity Fired Quantity Information From 24 To 18 Cancel Quantity UL cfr EA Remove Description Inject Reject Last Results Booster Pressure Operating Cost Resistance 0 36677 egulator Resistance 7 07562 Total Resistance 4 4433 Orifice Area 4 56 Fixed Quantity Fited Quantity Information From 23 Quantity EN Ectro Descriptors Inject Reject Booster Pressure Operating Cost Resistance Regulator Resistance Total Resistance Orifice Area Figure 41 Fixed Quantity Booster Fan 49 Within the Fixed Quantity dialog box there is the option of specifying the branch as an Inject
80. g fan curves created in DuctSIM to VnetPC Pro Fan File Manager a Under the File menu select New b Select VnetPC Pro Fan Curve File and then select OK c Select units the press OK d Goto the Tools drop down menu and select Import DuctSIM Curves e Find the DuctSIM fan curve file in the Windows dialog box f Hi light the desired fan curve file and select OK g The DuctSIM fan curve files will then be transferred into VnetPC Pro Fan File Manager h Under the File menu select Save As the save the file like any Windows application with the fdb file type to be useable in VnetPC Pro files 3 5 Fixed Quantity Tool The user may add a fixed quantity to a branch in the Branch Input Fixed Quantities or the Schematic views In the Branch Input view the Fixed Quantity tool is enabled by selecting Branch gt Fan or Fixed Q or by double clicking in the F Q column This tool is used to simulate control of airflow and will determine the resistance pressure drop and orifice area for a regulator or the operating pressure of a booster fan A fixed quantity can be allocated to any branch that does not contain a fan The user adds a fixed quantity in the Fixed Quantities view see Figure 40 by selecting Fixed Q gt Add Fixed Q or by clicking the RiFan tool button This fixed quantity may then be edited or deleted later by selecting Fixed Q gt E
81. g it in one direction or another The columns can be removed or added by selecting View gt Columns This is useful so that the items on a view can be limited to only those parameters actually used in the simulation Figure 60 shows the columns dialog box for the Branch Input view Users may view all the branch groups selected groups or active group in the Branch Input and Branch Results views as shown in Figure 61 This function allows the user to sort the data by branch groups for easier viewing 66 Select Columns to Display Available Columns Columns to Showy TUNA Tyne To Resistance Pressure Drop Quantity Friction Factor Resistance per Length Length ae Length Area File GoTo Edit View Branch Tools Window Help Figure 59 Selected Branch Group being Displayed in Branch Input View 67 4 6 Window Menu The Window menu allows the user to navigate through the program easier when multiple views are opened Once the menu is selected the user has the following options to select New Window Cascade Tile Arrange Icons and the list of currently opened windows see Figure 62 By selecting any of the currently opened windows from this menu the user will immediately be redirected to the view This prevents the user from having to search through the icons in VnetPC for the desired view If more than nine windows are opened an option at the bottom of the menu will be displayed This option opens a separate dial
82. he new branches according to length ratio User entered data for Shock Resistance Fan Fixed Q and In Atmosphere will only be retained by the From branch The user cannot create branches in the 3D view Branches can only be input in the plan and section VIEWS Users experienced with previous versions of VnetPC have indicated that confusion can arise if two or more branches are entered with identical From and To junction numbers VnetPC Pro checks for this condition during data entry and will not allow duplicate branches However the user can effectively connect any two junctions with parallel branches by inserting intermediate nodes The Plot Existing Junction tool allows the user to plot the locations for junctions entered in the Branch Input view This tool will not allow new junctions to be added and only allows existing junctions to be plotted whether previously defined or not The user can only plot existing junctions in plan view The Fan or Fixed O tool allows fans or fixed quantity values to be allocated to existing branches If a fan or fixed quantity already exists in the selected branch then the fan or fixed quantity attributes for that branch are displayed The direction of flow is based on the From To node input data By selecting a branch with the Create Fan tool the following dialog box appears shown in Figure 15 The user is then allowed to select a fan or fixed quantity for the assigned branch The user cannot create
83. he original resistance value In previous versions of VnetPC shock loss resistances were only added as separate resistances in the model Changing the Parallel Factor did not affect the overall shock loss resistance of a set of branches For instance if a single branch had a shock loss of 1 0 P U and the user applies a parallel factor of 2 creating two parallel branches each with a shock loss of 1 0 P U instead of a single branch the new overall shock loss resistance of the combined branches would still have been 1 0 The user would have had to change the shock loss from 1 0 to 0 25 in order to properly represent the new branches VnetPC Pro accounts for this change in the model and the user need not re enter new shock losses every time parallel factors are changed 3 3 2 Branch Input View Branch characteristic data can be entered and modified in a manner typical of Windows based spreadsheets in the Branch Input view A branch can be added deleted or inserted by selecting the respective command under the Branch menu If a new model is being developed or branches are being added from this view the user can select Add Branch under the Branch menu When the first branch in a network has been entered additional branches are added automatically by typing Enter at the end of the last row in the Branch Input view Additional branches may also be added by typing Shift Enter at any point in the Branch Input view Once data has been entered in
84. helpful to draw the Schematic lines along the centerlines of airways Not all airways need to be drawn Common airways arranged in parallel such as those in a coal mine should typically be drawn as one line Care should be taken to ensure all air courses are properly represented in the ventilation Schematic An excessive number of airways can result in model inefficiencies and lead to a greater potential for errors Large networks require more time to execute and will not necessarily provide increased accuracy The AutoCAD Schematic does not have to be exact since it can be adjusted in the VnetPC program for evenness spacing and alignment Figure 69 through Figure 73 illustrate the four levels with the network lines drawn on overlying layers y OIST SHAFT V N e amp ras ESCAPEWAY Y EXPLORATION 2 FRESHAIR RAISE 1400 Level 1 FRESH N MAIN RETURN AIR RAISE 12 DIA E roe SAN NOEL 9p TO SURFAC MAIN WEST RETURN y TO SURFACE 5 RETURN AIR DRIFT lS i FILLED STOPES Jl P ry vie a FILLED STOPES Figure 67 1400 Level with Wire Frame Drawn 73 IST 1600 Level No 2 F ARAISE No 2 F ARAISE 800 REFUGE STATION EXHAUST RAISE EAST RAR 1660 A STOPING AREA AUX VENT Figure 68 1600 Level with Wire Frame Drawn HOIST SHAFT aa Nas ORE PASS N 1800 Level ALNA ROCK PASS N p ESCAPE RAISE
85. ically obtained from survey results or empirically computed using suitable friction factors and airway geometry It is most common to use this data type for extending existing airways without requiring the calculation of k factors This is only effective if characteristics such as the dimensions of the opening roof control methods and airflow obstructions are consistent along the length of the airway Resistance per length values are typically calculated as the average of the values of 19 several similar airways This will eliminate anomalies that commonly occur during ventilation surveys and yield more realistic results than values from a single branch or estimated using a table of k factors The process for entering R L values is identical to that for entering k factors in both the Schematic view and the Branch Input view To facilitate input of R L values a user defined list of R L values may be accessed by clicking the Select R per L button on the Branch Data dialog box The Select Resistance per Length dialog box will appear as shown in Figure 7 Use the selection pointer and left mouse click on a cell in the row of the desired R L value and press OK to apply the R L value to the branch Note Resistance per length values are input per 1 000 units ft or m Select Resistance Per Length User Defined aluez Resistance EZ per Length escriptio J Cancel R 1000ft Units F U per 1000 ft Figure 7 Resistance
86. ices can also become factors in the design criteria The following flowchart illustrates a typical approach to integrating design and modeling into developing a mine ventilation plan Planning Exercises Update Netu ork Proceed to Next Time Phased Anahst Optimize Major F are Aras Cycle Through C lim atic Simulatio rs Required 110 7 2 Glossary of Terms Air Power Airflow Anemometer Area Atkinson Balanced network Bleeder Booster Fan Bore hole Branch Brattice Equivalent Length The power required to overcome the resistance of an airway or series of airways This does not include any fan or motor efficiency Air Horse Power cfm x inch w g x 52 33 000 Air Power cubic meters per second x kPa Measurement of air quantity per unit time through an airway Given as Imperial Unit cubic feet per minute or SI cubic meters per second An instrument used to measure air velocity The instrument normally uses rotating vanes hot wire or ultrasonic type sensors The cross sectional area is defined as the area of the drift perpendicular to the direction of airflow John Job Atkinson wrote the classic paper On the Theory of the Ventilation of mines presented in 1854 in which he derived what is now known as the Atkinson s equation p k l per v 2 A and the Atkinson s friction factor k A ventilation model in which both airflow and pressure distributions follow both of Kirchhoff
87. is applied to the flows of all the branches in the mesh This is performed for each mesh in the network 4 This process is repeated iteratively until Kirchhoff s Second Law holds to a prescribed level of accuracy for every mesh in the network The resulting network is then balanced 102 7 1 2 Kirchhoff s Laws The algebraic sum of the volume flow rates entering and leaving each junction equals zero Pseudo compressible flow can be simulated by fixed quantity injections or rejections of air at any junction Example 33 1 23 5 56 6 0 0 The algebraic sum of pressure drops along any closed circuit equals zero Example 10 20 35 65 0 7 1 3 Units and Conversions The following table provides a list of basic conversions between Imperial and SI units for parameters commonly found in Ventilation analyses Imperial System SI System Value Units Value Units 1 0 ft feet 0 3048 m meter 1 0 ft 2 square feet 0 0929 m 2 square meter 1 0 ft s feet per second 0 3048 m s meter per second 1 0 ft min feet per minute 0 00508 m s meter per second 1 0 143 cubic feet 0 02832 m22 cubic meter 1 0 ft43 s cubic feet per second 0 02832 m 3 s cubic meter per second 103 1 0 t43 min cubic feet per minute 0 000472 m 3 s cubic meter per second 1 0 lb mass pound mass 0 453592 kg kilo gram 1 0 bf ft 2 psf pound per square foot 47 880 N m 2 Pa Pascal 1 0 bf in 2 psi pound per square inch
88. istance column reports the total of the branch input resistance and the resistance of 57 any regulation resulting from fixed quantities Open the Fixed Quantities view to see the individual resistance values cy VinetPC Pro VnetPC PRO User Manual File GoTo Edit View Branch Tools Window Help ee SS a 5 Sle ole zie gt une VnetPC PRO User Manual Branch Results Pressure del dela pisar a Welo eae From FBR ice ae Drop Description Branch ID P U m in wq R a ee A INIA r oosaaz 1068 62 _ om 4 Si s o ar ass A as amas 06 T et 4 ao eos aes T me s 2 El ap oasis es odo af INIA o o AMI lt lt lt IE sos te od a os ss eos 2as ess 8 n MS IR so 2 ow e FR f ows so so ou a fo o HA A iso ste 0 00767 eej asa ae ea a ESTE w em A IA ICE ear ae a T e orj r ar e A AS A AA For Help press Fl Figure 49 Branch Results View 4 4 4 Fixed Quantity Information Fixed quantity input and output data are shown under the Fixed Quantities view refer to Figure 40 This view lists branch number junction From To whether the branch is designated as inject reject I R booster pressure regulator resistance regulator orifice area input branch resistance total resistance of the branch 1f regulated and description for the fixed quantity 4 4 5 Displaying Results in the Schematic View The on screen Schematic view 1s perhaps the most user friendly way to inpu
89. jects This tool allows the user to edit the details of an object Surface 1440 Level 1600 Level 1800 Level 1920 Level 8 2000 Level ___ E Oo da ww N fe E Plot Junction 3 D Spin Plan View Cross Section Long Section 3D View All Groups Selected Groups Active Groups Edit Groups Group Selection Menu New File 98 This tool will relocate any existing junction node to another location selected by the user The user may right click on a junction to edit the x y and or z coordinates or the user may left click on a junction and then select a second junction to snap the junctions together This will eliminate the first junction and attach its branches to the second junction This tool allows the user to rotate the schematic The mouse is used to drag the schematic around a central axis to clarify the view of the network View all groups layers in the plan view Change the view to the cross section Change the view to the long section View the schematic in three dimensions The schematic can then be actively dragged Branch and junction data can be edited in three dimensions View all groups layers in the current view View only the selected groups layers in the current view View only the active group layer Edit the layer attributes Quickly change between groups Allows users to create a new VnetPC Pro File or VnetPC Pro Fan Curve File
90. kage paths VnetPC Pro will automatically close those branches connected to the surface as long as the user specifies them as being In Atmosphere The option to select the surface state of the various network branches is located in both the Schematic and Branch Input views refer to Section 2 10 4 5 3 1 2 Junction Numbers Junction numbers must be assigned to each junction in the schematic Valid numbers are whole integers from 1 to 10 000 VnetPC is capable of selective viewing and printing of branches interconnected to any specified range of junction numbers VnetPC will automatically allocate junction numbers for new branches drawn in the Schematic view or for imported data from a DXF file 3 1 3 Schematic Layout Three methods can be used to enter the schematic into VnetPC 1 Draw the schematic in a CAD or mine planning program established as a unique layer named by the user and import to VnetPC This method is typically adopted when the user wants to overlay the ventilation network on a mine plan within a CAD program 2 Directly plot the network on the screen using the VnetPC drawing tools acceptable for smaller networks and where precise geometry is not necessary 3 Numerically enter the coordinate data in tabular form or copy the coordinate data from a spreadsheet and paste into the Junction Data view Note Scaling and Offset of Coordinates during DXF import VnetPC supports real world coordinates and will generally im
91. ls and Tutorials Full online support at www mvsengineering com Direct graphic printing and multi colored plotting Export DXF files to CAD and mine planning programs attribute exported specifically chosen Four input data types for branch resistance Steady state contaminant distribution analyses Fixed quantity tool Color coding of branches for range of parameters airflow pressure etc Dual parameters display in schematic view Cut copy paste features for data exchange within Windows Variable frequency drives fan curve adjustments for density and frequency RPM Edit branches in multiple views Fan curve graphics with current operating point displayed Import fan curves created in DuctSIM Transient time calculator based on user selected path Branch templates Branch groups enables user to turn specific groups off on in display Multiple branch selection and editing Editing single or multiple branch properties with templates Scroll wheel zooming Zoom to cursor Pan with center mouse wheel Fan stall warnings Shock loss calculator with reference material Isometric 3D editing capabilities Branch and fan power usage 2 4 Minimum System Requirements of VnetPC IBM Compatible Computer running Windows XP Vista or Windows 7 Intel Pentium class processor or above 512 MB RAM Memory 100 MB Hard Disk Space for the VnetPC program additional for Adobe Acrobat Reader CD DVD Drive USB Slot HASP Key VGA Display 2
92. mally not necessary because branches drawn in blank areas of the screen using Create Branch will automatically be assigned From and To nodes junctions and numbers These default numbers can be changed as required The user cannot create nodes in the 3D view Nodes can only be input in the plan and section views Note that the user can select Preferences gt Junction Creation to change the starting node number refer to Section 2 10 4 3 The user may also the edit junction data by right clicking on a junction with the selection pointer and selecting Junction Data The following dialog box will be displayed see Figure 14 where the user may change the junction number and edit coordinate data Junction Data Junction Number fi s Coordinate Y Coordinate Z Coordinate Default 10000 Figure 14 Edit Junction Dialog Box 27 The Create Branch tool allows new branches to be drawn The program automatically allocates junctions at the start and end of these branches unless the user clicks on an existing node If an existing airway is used for a starting or termination point then the branch will be divided and a new node will be added The divided airway will be represented by two new branches one branch that retains the From junction and one that retains the To junction from the original branch The user entered pressure loss fixed resistance and length values from the old branch will split between t
93. mating because p Q data refers to actual measured data specific to a particular mine location For this reason VnetPC Pro does not allow application of p Q data by using Branch Templates If the user tries to apply or make a Branch Template by using the p Q setting p Q data will not be applied New branches will only contain data from the selected fields Since neither pressure nor quantity is listed as one of the fields to be applied in the Template Fields dialog box they may not be added to branches using Branch Templates 3 8 Transient Time Calculator The transient time calculator is used to calculate how long it will take for a particle to travel through a defined section of the network This time is determined using the air velocity which was calculated from the airflow quantity and the length of the branches The calculator is accessed by selecting Tools gt Transient Time In this dialog box shown in Figure 48 the user must start by entering a series of junctions to create a path that will be traversed by the particle After this is done the user must enter the average cross sectional area and length values of the individual branches in either the Branch Input view or Schematic view if this information has not already been entered The program will extract the pertinent airflows lengths and areas from the branch data Once the user has input the dimensions of the branches the total time to traverse the path is computed by
94. meter Per and cross sectional area A This data type computes branch resistance using an empirical formula known as Atkinson s equation expressed below in Equation 2 y ELH Leg Pe Equation 2 CA Where R _ airway resistance Practical Unit or Ns m k friction factor Ibf min ftx10 or kg m L length of airway ft or m L q equivalent length of shock loss ft or m O A area f or m Pe perimeter of airway ft or m c constant Imperial 52 and SI 1 VnetPC verifies each entry as it 1s input and if invalid requests re entry It should be noted when inputting a value for k factor in Imperial Units into the Branch Data the 10 factor must not be included in the entry Hence for a typical airway with a k factor of 65 101 Ibf min ft the user would enter only 65 Note that VnetPC uses a constant of 52 not 5 2 in the Atkinson 18 Equation This allows the Atkinson friction factor to be entered directly without including the 10 factor The resulting unit is termed the Practical Unit PU This same unit is obtained from the Square Law by using milli inch w g thousandths of an inch w g and kcfm thousand cubic feet of air per minute To facilitate input of friction factors a user defined list of k factors may be accessed by clicking the Select K factor button on the Branch Data dialog box The Select Friction Factor dialog box will appear as shown in Figure 6 Use the selecti
95. n by selecting Fan gt Add Fan or by clicking the add fan icon In the Schematic view a fan or fixed quantity is added using the Fan Tool l and selecting a branch with the Fan Tool cursor 3 4 1 Fan Location and Flow Direction 39 A fan can be located in any branch that does not contain a fixed quantity and vice versa The branch number and junction numbers dictate the fan location The order in which the junction numbers are entered defines the direction of the fan To view or edit or add to the fans in the model the user may use the Fan Input view 3 4 2 Fan Type Any fan can be entered with either a fixed pressure or with a characteristic curve of pressure against volume flow The fixed pressure and description of the fan can be entered in the Fan Data dialog box illustrated in Figure 31 If a fan curve is not input this dialog box allows the user to enter a fixed fan pressure regardless of quantity If a fan curve is input it will override the fixed fan pressure input Users may change the operating status for fans in VnetPC models without removing them When a fan status 1s turn Off the program will use the entered branch resistance and it will not assume or add resistance to the airway created by the fan dampers closing or by a non operating idle fan To simulate the resistance of an idle fan or closed dampers the user must modify the resistance in the branch for the arranged conditions Fan Data Fan In
96. nch Number l Dual Parameters a Airflow Direction Plot a Line Plot This setting displays the airflow velocity in each branch calculated from the latest model execution shown in ft min or m s This setting displays the resistance in each branch calculated from the latest model execution shown in P U or Ns m This setting displays the Air Power Loss in each branch calculated from the latest model execution shown in hp or kW This setting displays the Operating Cost in each branch calculated from the latest model execution shown in yr This setting displays the branch number in each branch This setting allows the user to display two different branch parameters at the same time The user may choose to view any two of the following parameters calculated from the latest model execution pressure drop airflow quantity airflow velocity resistance Air Power Loss Operating Cost Branch Number Contaminant Flow and Contaminant Concentration This setting displays the airflow direction in each branch calculated from the latest model execution This setting allows the user to view the schematic without any parameters or airflow direction arrows displayed The Branch Input view contains the following additional icons not contained in the Schematic view 100 Paste Pastes the copied information into the desired cell s d Find Branch pa Fan or Fixed Q Locates a branch by finding both respective ju
97. nctions or by finding the next occurrence of one junction Adds a Fan or Fixed Quantity to a branch or edits the existing Fan or Fixed Quantity in a branch The Fixed Quantities view contains the following additional icons tools not contained in Schematic view and Branch Input view ba Add Fixed Q Y Edit Fixed Q Adds a Fixed Quantity by allowing the user to enter the From and To junctions of the desired branch Allows the user to edit the properties of an existing Fixed Quantity The Fan Input view contains the following additional icons tools not contained in Schematic view Branch Input view and Fixed Quantities View E Add Fan Ol Edit Fan x Delete Fan ics Edit Curve Adds a Fan by allowing the user to enter the From and To junctions of the desired branch Allows the user to edit the properties of an existing Fixed Quantity Deletes the selected Fan Allows the user to Edit the Fan Curve for the selected Fan 101 7 Appendix B Quick Reference and Glossary The VnetPC Pro program is a self contained Windows based package of programs which combines the simplicity of Windows data representation and the reliability of the VnetPC program VnetPC Pro is designed to assist mine engineers in the planning of subsurface ventilation layouts Given data that describes the geometry of the subsurface network airway resistance or dimensions and the location and characteristic curves of fans the program will provide detailed listi
98. nected Once the wire frame diagrams are drawn they will look like the pictures in Figure 76 through Figure 80 in plan view Figure 74 1400 Level VnetPC Pro Schematic T1 Figure 75 1600 Level VnetPC Pro Schematic Figure 76 1800 Level VnetPC Pro Schematic Figure 77 1920 Level VnetPC Pro Schematic Figure 78 2000 Level VnetPC Pro Schematic 5 2 3 Exporting the DXF File Once the line diagrams are completed a DXF file needs to be generated This is done in AutoCAD by selecting File gt Save As Be sure to select the DXF option under the File Type drop down menu Also make sure that the DXF file is saved in the proper location The Save As dialog box is shown in Figure 81 for the tutorial example 79 amp Save Drawing As sks AXE ve Tod Preview This folder is empty j Update sheet and view thumbnails now tutorial dwal File name Files of type AutoCAD 2010 Drawing dwg Figure 79 AutoCAD Save Drawing As Dialog Box Once a DXF file has been saved the AutoCAD program can be closed 5 3 Working in the VnetPC Program 5 3 1 Setting Up the VnetPC File The New File view 1s the first view presented to the user when a model is opened For a model to be initiated the user should select File gt New which brings up a dialog box illustrated in Figure 82 This dialog box provides the user the choice of generating a fan data base or VnetPC do
99. ngs and graphical representations of the desired parameters The following Quick Reference and Glossary are meant to assist the user in ventilation planning and design These references were not intended to be comprehensive guides but rather clarify some general ventilation principles and concepts 7 1 Quick Reference 7 1 1 Background Theory The VNET program has been developed based on the assumption of incompressible flow and on Kirchhoff s Laws 1 The algebraic sum of the volume flow rates entering and leaving each junction equals zero Pseudo compressible flow can be simulated by fixed quantity injections or rejections of air at any junction 2 The algebraic sum of pressure drops along any closed circuit equals zero The code utilizes an accelerated form of the Hardy Cross iterative technique to converge to a solution The procedure is as follows 1 The code scrutinizes the geometry of the ventilation network and constructs a number of closed meshes the minimum number being equivalent to the number of branches minus the number of junctions plus one Each branch in the network is represented in at least one mesh and in order to minimize computing time each mesh contains no more than one high resistance branch 2 For every mesh an airflow quantity correction factor is calculated using airway resistances and fan pressures The program estimates an initial airflow and the simulation is initiated 3 The airflow correction factor
100. ntaminant in Contaminants or Schematic view or by pressing the Execute Contaminant button located on the Tool Bar After executing columns labeled Contaminant Flow and Contaminant Concentration will update with the results of the model execution 3 7 Branch Template The Branch Template feature equips users with the ability to apply data to individual or multiple branches This will likely become the most common way to modify multiple branches at once Users define individual branch data properties using a Branch Template see Figure 45 After a Branch Template is defined users may apply this to a single branch or multiple selected branches Users can locate the list of templates by selecting Go To gt Branch Template U VnetPC Pro VnetPC PRO User Manual File GoTo Edit View Template Tools Window Help Dae SO B wej VnetPC PRO User Manual Branch Template Friction Resistance h Template Template D Resistance Factor Perimeter Parallel Pair Hame Description Type PU lbf per Length Fadior min ft aix R1000 E e WA WA _WA T NAO NAL _WA NA 4 Ram WA RNA WA Wal T WA NA For Help press Fl Figure 43 Branch Template View Branch Templates allow users to apply either complete branch data or selected branch data Using Template Fields see Figure 46 users can select which fields of data will be changed when the template is applied The Template Fields dialog box can be accessed by choosing
101. o Fan File Manager ooccccccnnccncccnnnnnnnnnonnnnnnnnnnnnnnnos 47 SO SPM ANY OO bip te tesa ascaabosaueoca pose A TR 47 3 6 CONTAMINANT DISTRIBUTION ANALYSIS DATA drid dota iaa 50 SF BRANCH TEMPLATE aid a 51 20 TRANSIENT TIME E ALCULA TOR tods 53 OPERATING THE PROGRAM cosas naaa 54 41 MANAGE NETWORK FILES ta a A A A A ai 54 4 2 DATA CONVERSION PREVIOUS VNETPC VERSIONS coooccconnoccnnnnoconononcnnnnononononconononocnnnarononnnccnnnanonnnnanononaninos 54 AS EXECU VENTILATION SIMULATION A A nea Beiteeneees 54 AA VIEWING THE RESULTS OFA SIMULATION 1 A a 55 4 4 1 e ger ee eee a ae RES Rae RCI PIR AEE SRST AR A SPE eo ACS ERE rs WV Ree ea VENT 55 4 4 1 1 Too Many Fixed Ouanna lacio 56 4 4 1 2 Blane Omitted m Messe lec OL A isc 56 4 4 1 3 No Mesh Found Tor brad arta daa atan 56 4 4 1 4 Hernon Cmt Excel einir tl OEE 56 4 4 1 5 Locate Enorm Schemat LOOM asi E E TE 56 4 4 2 SA O E A EER 57 4 4 3 Brane ERES ratita a aA Or ASEE E E EA dl 4 4 4 ExcaOiantity Information olaa 58 4 4 5 Displaying Results in the Schematic VieW ssssssseeecececeeeecccaaaasseseseeeeeceeeeeeeeeeeesuasseseseseeseeeeess 58 4 4 5 1 fed ot Wt A A Oe ee 58 4 4 5 2 ZOONEN A A Pas nse Pr ea se tas anal ahaa a cana pecan acs eta a ene ad ete tet aaa 64 4 4 6 WUC HONE e AAPP eaa cacehateooennsiiet a gba vevannentecyuig a A A 64 4 4 7 Pristine Ouro UG Data oeio a ern en dan ectadinan niet Aish cnt hahaha nn tan As ales adtac dedi 65 4 4 8 Plo
102. ocity pressure drop air power loss operating cost gas flow results gas concentration and resistance Color Ranges be accessed by selecting Preferences gt Define Colors and then selecting the desired parameter range to be modified The Color Range dialog box for quantity is shown in Figure 27 Color Range allows for branches to be color coordinated according to the magnitude of the value displayed The values entered under the range column represent the maximum value that may appear with that color For example in Figure 27 branches will be colored black for values between O and 10 Likewise branches will be colored bright green for values between 50 and 100 Color Ranges Parameter Quantity Range U 10000 kctrn Color Ranges Bright Blue 5 1000 00 pink Sample fe 100000 eyan Same Figure 27 Color Range Dialog Box 38 Use Color Code refers to the specific branch codes In Branch Data dialog and Branch Input view the user may select from a list of airway types codes Default Intake Return Neutral Active and other user defined types The Branch Code colors may be changed in the Schematic view by selecting Preferences gt Define Colors gt Branch Codes as shown in Figure 28 By selecting Preferences gt Use Color Code the user may define the branch colors by Branch Code Branch Codes Branch Code Names and Colors _Sample p Default Black gt Cancel
103. og box will appear showing the full list of available windows Dae S O ejer aaa FR PEAR LEN Arrange Icons 1 VnetPC PRO User Manual Branch Input 2 VnetPC PRO User Manual Branch Results 3 VnetPC PRO User Manual Fixed Quantities 4 VnetPC PRO User Manual Branch Template 5 VnetPC PRO User Manual Fan Input 6 VnetPC PRO User Manual Fan Results 7 VnetPC PRO User Manual Junction Data Y 8 VnetPC PRO User Manual Schematic 9 VnetPC PRO User Manual Contaminants More Windows Figure 60 Window Menu Selecting New Window allows the user to open a second copy of the selected view This may allow the user to observe the same viewing window in multiple different ways at the same time For example 1f the user wants to view the Schematic in two different mine locations at the same time to compare airway profiles while in the Schematic view they would select Window gt New Window and adjust the viewing perspectives of both schematics accordingly If changes are made in one of the views they will update in the other view If the user selects Cascade all open windows will arrange themselves in cascading format see Figure 63 68 Goto Edt yew Fan Toots Window Help sus haba S ag ERAS REE BER SERBS RR falo fal SEALS Na Au Po ler alt Fan Fan Ar Operalmy Coro cy Pressure Duantty Power Cost Branch D Power inwag Reim mep yr Figure 61 Cascade Windows By
104. on pointer and left mouse click on a cell in the row of the desired k factor and press OK to apply the k factor to the branch Select Friction Factor User Defined Values Friction Factor lbf min ft 4x ETA No Selection C E AA Units BF mir ide 10 10 Figure 6 Friction Factor Dialog Box The Select Friction Factor feature allows the user to enter a k factor value and description for each variety of airways to be modeled with the k factor data type These stored values can then be recalled rapidly to populate resistance data for future branches The Select Friction Factor dialog box can also be accessed in the Branch Input view from the Branch drop down when a k factor field is selected An additional way to access the stored friction factors from the Branch Input view is to double click on the edge of a cell for the friction factor of a desired branch Atkinson Friction Factor data type k factor may also be entered by using Branch Templates Please see section 3 7 for more information on Branch Template data entry K factors may also be entered in the form of Branch Templates 3 3 1 4 Resistance per Length Data Format The resistance per unit length R L data type allows the user to input an empirical resistance per length value for the airway and requires branch length Equivalent length of shock losses may also be entered if desired Resistance per unit length values for the airways being modeled are typ
105. or Reject branch This tool is used to add or remove air from selected junctions to account for compressibility effects ducts compressed air lines or areas of the facility not otherwise represented in the network For example as air passes down a shaft it is compressed due to autocompression Since VnetPC assumes incompressible flow this compression may need to be modeled separately by removing air rejecting from the model at the base or along the length of the intake shaft Note that air will probably need to be injected in deep mines to account for the effects of expansion as the air rises This tool is only used to assist the user by flagging the inject reject status of the fixed quantity and does not change the functionality of VnetPC Pro in any way 3 6 Contaminant Distribution Analysis Data The contaminant distribution utility incorporated in VnetPC utilizes results of the network exercises to evaluate contaminant concentration and gas flow distributions The user specifies locations and magnitudes of contaminant sources in the Contaminants view refer to Figure 44 The program uses airflows from the last execution of the ventilation simulation to calculate contaminant flow assuming steady state conditions The program also assumes fully turbulent flows with complete mixing C VnetPC Pro VnetPC PRO User Manual File GoTo Edit View Tools Window Help O ggl BE Ae 4 VnetPC PRO User Manual Contaminants a fam Emission
106. ould be noted that only undefined junctions may be deleted in Junction Data view Junctions created in Junction Data view will have undefined default coordinates without branches attached to them E VnetPC Pro VnetPC PRO User Manual File GoTo Edit View Junction Tools Window Help gt ES f2 E we VnetPC PRO User Manual Junction Data E oases cas ae Saad No Attached E ae here ft ft ft m in wg j A TE E E E E A E s ro oso aoo 3 0 aso asmo 2 A sees E E CA E EE For Help press F1 Figure 56 Junction Data View 4 4 7 Printing Output Data The output data tabular views and the Schematic can be directly printed by either clicking the print icon on the tool bar or by selecting the Print Active View subheading under the File menu The user can also specify a print range in the Print Dialog box Prior to printing the output it can be previewed on the screen by selecting File gt Print Preview The printer can be reconfigured by selecting File gt Print Setup This can be particularly helpful when changing the paper orientation from portrait to landscape Often the Schematic and Branch Input data are better represented by printing in landscape mode Different output devices can be specified using the Print Setup option as long as the device driver has been loaded within Windows 65 4 4 8 Plotting Output Data Plotting is managed the same way as printing exc
107. own dialog box on the Toolbar and then by pressing the Active Group icon o 88 Group Filter EJE E 2 8 08 6 1900 Level o 2 1400 Level 3 Surface 4 1440 Level 5 1600 Level 7 1920 Level 8 2000 Level Figure 90 Illustration of a Single Group Level and Group Filter In this case a node will be inserted in branch 48 32 To insert the junction the user selects the Create Junction option from the Tools menu or uses the Create Junction icon located on the Toolbar The inserted node is displayed on Figure 93 Figure 91 Inserting a Junction 89 The VnetPC program will assign the junction the next free junction number and automatically place the newly created branch 50 32 on the 1800VENT group with all of the attributes belonging to that group 5 5 Defining Branch Attributes Resistances Branch attributes can be defined or modified through either the Schematic view or the Branch Input view Because all subsurface airways have some resistance each branch should have a resistance value assigned to it The exception is if the branch is being used solely for graphical representation To define the attributes or resistances for each branch select the Edit option from the Tools menu use the Edit icon located on the Toolbar or right click with the pointer and select Branch Data from the drop down menu and the Branch Data see Figure 94 dialogue box will open All data that can be modified in this dialog box can al
108. pacing that is too dense to display a message box will appear and the user must input new data A tag at the bottom of the dialog box allows a snap feature to be enabled or disabled If enabled then any new or moved nodes will be snapped to the grid 35 Grid Spacing M Show amp Gridlines 2 Spacing 1000 Onin 0 4 Show t Grdlines Y Spacing 1000 Y Onin 0 Z Spacing 1000 2 Onin 0 Always Snap to Grid Figure 24 Grid Spacing Dialog Box 3 3 4 3 Junction Creation When branches are added in the Schematic view VnetPC will normally add node numbers in an ascending sequence starting from the lowest available number By selecting Preferences gt Junction Creation the user may disable the feature that uses the lowest available number and input a number to commence the node sequence Figure 25 illustrates where a user may define the next junction value The program internally checks node numbers to ensure that a node number is only used once New Junction Number Nest Junction Number Cancel 4 Use Least Available Number Figure 25 New Junction Number Dialog Box 3 3 4 4 Importing DXF Files from CAD and Mine Planning Programs VnetPC allows the user to import a network or level from a CAD or mine planning program using a DXF file to transfer the data To import data the user must select Tools gt Import DXF in the Schematic view A browser window will be displayed for the user
109. pear allowing the user to change the location of the junction The users may also change the elevation in the Junction Data view by editing the z coordinates If desired group names can be modified Initial names are defaulted to the layer names imported from AutoCAD Group 1 entitled Default is the initial default level This level can be deleted or re named to suit the user If this level is renamed then the z coordinates for this level should be modified from 0 to the desired level elevation It is important to note that only the active group can be modified by the user the user cannot construct branches in non active groups Furthermore only one group can be active at any one time although all or multiple groups can be displayed Figure 89 shows the modification of the elevation of node 32 on the ramp from 1800 Level to 1600 Level When a group is imported without an elevation defined then all of the nodes in that group will be defaulted to the mean elevation value However the elevation values can be easily modified to allow a ramp to extend from the base of the model to the upper levels as displayed on Figure 89 Figure 87 Completed Cross Sectional View of Schematic Because this model was developed on a two dimensional plane in AutoCAD no elevations were imported into VnetPC If elevations were used in the AutoCAD drawing they would have been imported and the z coordinates would have been defined In the
110. port exact coordinates from CAD programs The exception is when the program has to apply an offset to the imported data and or scale the network because the coordinate range is too great for the VnetPC views coordinate values greater than 1 billion Any scaling or offset is identified to the user during the importing process For importing multiple layers or DXF files into the same network the initial offset and scaling information used for the first layer will automatically be applied to all subsequently imported layers 13 3 2 Descriptive Data Descriptive data consists of both required and optional information for documentation and program initiation This information is modified in the Model Information view The Model Information view allows data to be directly entered into fields as shown in Figure 3 File GoTo Edit View Tools Window Help Ome S o Model Data Title User Manual Mine Avg Fan Efficiency 65 Cost of Power 0 04 tkw hr Reference Junction 1 Avg AirDensityy 0 07 lb ft Units Comments Data Summary Branches 104 Fans Junctions 91 Fited Quantities Last Execution of Simulation Date 12 03 10 Iterations Time 11 01 27 Errors Modified Since For Help press Fl MODIFIED Figure 3 Model Information View The following subsections describe the input and required format for the data in the Model Information view 3 2 1 File Name A file name must be assigned when saving the file for
111. pressing the Calculate button on the Air Transient Time Calculator dialog box The user can store sequences that will be used more than once by using the Sequence List button available on the Transient Time dialog box 53 Air Transient Time Calculator Junction Number Sequence Current Sequence Ex 1 2 3 4 Sequence List Comments Results Quantity Total Time kctm Calculate Use Sir Travel Time data entry mode Figure 46 Transient Time Calculator Dialog Box 4 Operating the Program 4 1 Manage Network Files VnetPC utilizes conventional Windows protocol for managing files WnetPC files are searched for under the designated vdb file extension and fan files under the fdb extension Files may be accessed from the host computer or through a network system 4 2 Data Conversion Previous VnetPC Versions VnetPC allows import of files from previous versions of VnetPC VnetPC 2000 VnetPC 2003 and VnetPC 2007 To convert a file the user opens it normally executes the simulation and then saves the file in the new VnetPC Pro format It is important that the file to be converted has coordinates specified for all the junctions in the network If the user has not specified coordinates for all the nodes then errors will appear when the file is opened 4 3 Execute Ventilation Simulation Executing the program is accomplished by selecting Tools gt Execute Simulation This should only be done when the br
112. ption from under the File menu This will print whichever view is active Each view can be individually setup for printing in order to display all of the information desired on the page 108 Page Setup Print Preview Print Active View Ctrl P Under the Preferences Menu on the Toolbar the user can control the size and type of font and location of plot labels Orientation of the plot and size of the printable area is done in the Page Setup dialog box shown below This option is found under the File Menu Page Setup bhal Fax Properties Margins inches Left 1 Right 1 Lok Top 1 Bottom 1 A Cancel 7 1 11 Possible Design Criteria The purpose behind manipulating the ventilation model is to establish the total mine wide requirements to meet certain design criteria The design criteria are usually based upon the minimum amount of airflow required for the operation of equipment and to provide for comfortable working conditions for personnel underground Each piece of equipment operated underground should be examined to establish exactly how much airflow will be required by law for that equipment Every area of possible gas emission should be examined and estimates of the emission made to establish a minimum safe operating airflow to dilute that gas Predicted temperatures and relative humidity should be examined to ensure personnel are working in a safe environment Current regulations should be examined to
113. put Data OF From Cancel Pressure Remove Description Fan Curve Status Curve Edit Curve a On Off Fans in Parallel 1 Fans in Series 1 Last Results Pressure NAA in Motor Input Power Quantity H Ectfro Aur Power Curve Status A S Operating Cost Figure 29 Fan Data Dialog Box The user may enter a fan curve by selecting Edit Curve from the Fan Data dialog box illustrated in Figure 31 In the Fan Input and Fan Results views the user may enter a fan curve by selecting Fan gt Edit Fan Curve Additionally in the Fan Input view Fans may be added edited or deleted by selecting Fan gt Add Fan Edit Fan or Delete Fan respectively In the Fan Results view fans may be edited by selecting Fan gt Edit Fan Fan characteristic curves are registered by entering between two and twenty sets of pressure airflow data points see Figure 32 These points should be chosen such that they adequately represent the full extent of the 40 curve Users may add efficiencies for each of the fan curve points entered The program will use the entered airflow pressure and efficiency to calculate the Motor Input Power The program assumes a linear line between any two points on the fan curve Fans with characteristic curves can be entered under fan data or retrieved from the fan data bank Once the points of the fan curve are entered into the Fan Data Sheet the user can sel
114. r The user is required to input an average air density for the underground facility This value is needed to compute the orifice area for any regulators listed in the Fixed Quantities view The average air density parameter is also used to calculate shock losses added to branches 3 2 5 Notepad Comments There is a large text field available to enter a detailed description of the particular file Information may include a title summary of results and the specific details associated with that model This notepad is seen in the Model Information view Text may be entered directly in the reduced window or the comments section may be maximized by pressing the Edit key Users need to deactivate a modified field by choosing a new active field before attempting to save the file Changes made to an active field will not be retained when the file is saved Users may also make changes to the text field by selecting Tools gt Comments in any view 3 3 Branch Data 3 3 1 Branch Data Formats Each branch is defined by two junctions and by numerical data that indicate the characteristics of the airway Data may be entered in any of four formats The mouse can be used to copy and paste ranges of data between branches in the Branch Input view or from other Windows applications such as spreadsheets or other ventilation simulators Once data 1s entered into the program the data will remain until deleted or overwritten by new data of the same format
115. r Loss Operating Cost Resistance Branch Humber Contaminant Flow Contaminant Concentration Figure 52 Select Dual Parameters Dialog Box Figure 55 is an example of Dual Parameters being displayed on the ventilation Schematic in VnetPC For this example Quantity color coded Bright Blue was selected for Parameter and Pressure Drop color coded Bright Red was selected for Parameter 2 60 2 VnetPC Pro VnetPC PRO User Manual Schematic o 0 fel uned File GoTo Edit View Preferences Zoom Tools Window Help E X D gag Bl SAA MFE E PSAL Z F R e A a 7 L EJE 2 6e o A 8 2000 Level 12 1 545 4 AA ARS aja EA x 4654 z 1674 Dual Parameters Figure 53 Example of Dual Parameters Displayed on a Ventilation Schematic Define Colors This command allows color ranges to be specified for the different parameters There is a choice between sixteen different colors including black and white For a specified parameter range the network branches containing values within that range will appear on the screen and printed plotted on paper in the specified color A legend can be printed detailing parameter ranges and color assignments This option is useful to help identify high pressure drops or excessive operating costs in the branches within the network If the specified printer does not have one of the selected colors then the legend will automatically be omitted from the output Junction and relative pressur
116. r Size Air Power Loss Plot Labels Operating Cost Default Font Grid Settings Gas Flow Results Gas Concentration No Color Use Color Range __ Ue Color Code Branch Codes Resistance J U nctio n Nodes Ju nctio ME Junction Numbers Relative Pressure Symbols Display Labels Show VR Branches Background Color Line Properties il View edit branch code names and colors Line Plot MODIFIED Figure 93 Location of Branch Code in Drop Down Menu Branch Code Hames and Colors a eran fsa Sample Return Bright Red samp 6 Recre Black Sample Bright Green sample 8 JUnused Bick Same Set As Default Default branch code shown in bold test To reorder rows select a row and drag it up or down Figure 94 Branch Code Dialogue Box 91 Every ventilation network as with every mine must have at least one intake and one exhaust airway connected to the surface atmosphere The VnetPC program requires that the intake and exhaust portals and shaft surface connections be identified This system takes the place of the old method of creating zero resistance atmospheric branches connecting all surface junctions to some arbitrary atmospheric node To identify a branch as a surface connection the user must simply check the box next In Atmosphere in the Branch Data dialog menu In the Branch Data dialogue box see Figure 97 each branch can also be allocated a symbol airway
117. ranches 27 plot existing junction 26 plotting 68 power cost 14 preferences menu 60 print active view 67 print setup 67 relative pressure 64 resistance 14 results 57 scaling and offset 12 schematic 11 12 61 90 schematic view 20 30 60 selection pointer 25 setup procedure 9 shock loss tool 23 software encryption 8 square law 17 surface exhaust 12 surface nodes 36 symbols 65 system requirements 8 theory of VnetPC 7 transient time 55 tutorial 72 units 14 ventilation network 12 views 11 VnetPC 7 zoom tool 26
118. rconnecting branches some fixed quantities will be omitted from the mesh selection process Too many fixed quantities can mean that the model is over constrained with fixed quantities or that there are simply too many fixed quantities for the program to converge to a solution properly In the case of this error the number of fixed quantity or inject reject branches should be decreased before the network 1s re executed 4 4 1 2 Branch Omitted in Mesh Selection The branches that appear under this heading in the error screen were not included in the mesh formation process The truncated network is still evaluated but without the omitted branches Junctions connected to only one branch e g dead end branches usually cause this error If this message appears the network should be scrutinized and amended 4 4 1 3 No Mesh Found for Branch This message arises from the basic branch and mesh selection processes The minimum number of independent closed meshes required for every network is defined as number of branches number of junctions 1 If for any reason this value is not attained during the basic branch selection process or the mesh selection process this error message will occur The program is designed to continue evaluation of the network based on the number of meshes attained 4 4 1 4 Iteration Limit Exceeded The number of iterations for the Hardy Cross process used to solve the network is limited to 1000 iterations If after 1
119. references gt Parameter gt Dual Parameters see Figure 53 The user may also access Dual Parameters by selecting the icon on the Parameter Quick Select Tool Bar 59 2 VnetPC Pro VnetPC PRO User Manual Schematic e eE uned File GoTo Edit View Zoom Tools Window Help x De amp Be Parameter Quantity R B A F l M F L L L Aa o Define Colors gt Velocity Junction Range Pressure Drop Junction Creation Air Power Loss Letter Size Operating Cost Plot Labels Default Font Grid Settings Contaminant Flow Results Contaminant Concentration Resistance No Color Use Color Range Branch Number Y Use Color Code Line Plot Junction Nodes Dual Parameters Junction Numbers Relative Pressure Symbols Display Labels Show I R Branches Background Color Line Properties Line Plot Figure 51 Selecting Dual Parameters in the Schematic View After selecting Dual Parameters from the Preferences drop down menu a Select Dual Parameters dialog box will appear see Figure 54 With the drop down menus for parameter and color users may select which two parameters will be displayed on the Schematic The text colors displayed on the Schematic are user defined After the user selects the parameters and colors press OK Select Dual Parameters Parameter Color 1 Quantity ki Bright Blue Cancel 2 Bright Red None Quantity Velocit Air Powe
120. ription Surface State Neither Air Quantity 53 51 kcfm Data Threshold 0 005 Emission Aate kctra Default Value 0 005 Emission Concentration Contminant Flow Contaminant Concentration Figure 16 Branch Contaminants Dialog Box The Create Label option allows labels to be entered for specific views or groups see Figure 17 Attributes for these labels may then be changed using the Selection Pointer and the right mouse button or the Edit Tool The orientation of the label can also be rotated through 360 The user is allowed to specify a default text font and size under the Preferences menu Default Font All the common Windows fonts are supported and the text size may be adjusted over a large range for individual labels The user cannot create labels in the 3D view Labels can only be input in the plan and section views Add Label Group Number None Group Hame None Label Added Angle 0 Figure 17 Add Label Dialog Box The Zoom Tool allows the user to resize the view rapidly A section of the network may be expanded by dragging the mouse over the selected area while holding down the left mouse button The user can also press the left mouse button to zoom in or the right mouse button to zoom out Tool buttons in the Schematic view also enable the user to zoom in out S amp I and 29 zoom all El These buttons are typically required to allow zooming when using a different tool for the mouse such as A
121. rovide the proper Profile Type information for the Airways and check the box labeled Area Perimeter Auto Calculate The three profile types available in VnetPC are Rectangle Circle and Arched Each profile type includes a preview window that displays a graphical representation of the airway If improper or unrealistic dimensions are entered for the profile type an error message will appear in place of the graphical representation This feature may be deactivated by unchecking the box so that the user may enter the area and perimeter manually When the Auto Calculate Area Perimeter Tool 1s enabled the Area and Perimeter fields will become read only or grayed out in both the Branch Input and Branch Data dialog views This is indicated by changing the color of the text and fill of the field The user will not be able to edit this inactive field while the Auto Area Perimeter Calculated Tool is enabled Rectangle Profile Type The Rectangle Profile Type requires two user inputs height and width to calculate area and perimeter Maximum values for height and width are 60 meters or 200 feet However if the height to width ratio or width to height ratio is greater than 10 1 then an error massage will appear This is to prevent the user from accidentally entering unrealistic values Figure 9 displays the portion of the Branch Data dialog box that shows the Rectangle airway profile type Away Dimensions Profile T ype Rectangle Y
122. s been developed to allow networks to be constructed in both the Schematic and the Branch Input views The Schematic view allows the user to develop 3D models using a level scheme A level in VnetPC is defined as a group of branches falling within a user specified range of z coordinates may be thought of as a Group of branches that span a defined z range It is recommended that the user initially specify a series of levels to cover the entire vertical extent of the network The levels can be established with overlapping z ranges such that a shaft 31 or ramp level would represent a group of branches spread across the entire vertical extent of the mine Branches can be reassigned to any group regardless of the z values of the connected junctions New junctions created in the schematic view within an active group will default to the group z coordinate By selecting Tools gt Groups the user can add edit or delete groups from the network in the Branch Groups dialog box as shown in Figure 19 Groups may only be deleted if there are no existing junctions in the Group If the user tries to delete a group with existing junctions VnetPC Pro will display an error message accordingly and not allow the Group to be deleted Branch Groups Groups Group Group Defaut Z TEER Number Name pa Cancel 1390 0 Sho CE surface 10 0 JUN IE ECT TENES aS te00tever 1890 0 Show ShowAll_ s efe oof a gt f an Hide
123. s first and second laws This is a term applied to airways specifically designed to ventilate gob areas or abandoned workings This type of airway removes the highly contaminated air and places it directly into the exhaust This type of fan installation acts in conjunction with a main fan installation This is used mainly for district ventilation or expansion projects A small ventilation shaft usually installed with either a drill or raise bore machine This type of shaft is usually used for ventilation purposes only and is most often too small for equipment usage A single segment of a network model representing an airway or series of airways A wall usually constructed of cloth or plastic which is installed to stop airflow in an airway Generally more temporary than a stopping bulkhead This is used to add shock losses to an airway The additional airway length is equal to the resistance of the loss 111 Exhausting ventilation Fan Characteristic Curve Fan efficiency Forced ventilation Junction Kcfm K Factor Milli inch Network NVP Operating Cost This term is generally applied to ventilation systems operating under an induced negative pressure This has the effect of pulling air out of gob areas The operation of a fan 1s defined by the curve plotted by the pressure quantity s achieved in operation This curve can be modified by either changing the fan rotational speed blade angle or inlet van
124. s or 200 feet The center height is the distance from the center of the floor to the top of the roof The rib height measures the height of the side walls The rib height may also be automatically calculated from the Arch Factor The user must simply check the box next to Auto Calculate from Arch Factor and enter an appropriate value in the cell labeled Arch Factor If the Arch Factor is too low the program will prompt the user to enter an Arch Factor between a set of possible values Arch Factor values vary depending on the dimensions selected Figure 11 displays the portion of the Branch Data dialog box that shows the arched airway profile type 23 Away Dimensions Profile Type Arched Width 10 00 ft Center Height 10 00 Ft Auto Calculate Rib Height 7 41 1 from AnchF actor doch Factor 93 Area 33 00 FE Area Perimeter Perimeter 36 77 Ft Auto Calculate Length 1436 40 FE Z Auto Length Figure 11 Arched Profile Type 3 3 1 7 Shock Loss Calculator The VnetPC program incorporates a tool to calculate and apply shock loss resistances to branches This feature can be activated for each branch through the Branch Data dialog box in the Schematic view or the appropriate column in Branch Input A shock loss resistance may be added to any branch in the ventilation model This feature can be enabled or disabled at any time in the ventilation model and when disabled will retain the shock resistance value b
125. so be modified in the Branch Input view Branch Data ID 53 From 02 To Swap FromTo Group Name 1800 Level Descriptions Hote 1 Resistance Data Type p G Pressure Drop 6 0 rir wg Make Template Quantity 10 00 kcfm Fan Fixedd ME Shock Resistance 0 P 0 Contaminants Parallel Factor 1 Cale Shock Loss Away Dimensions Branch Parameters Profile Type Arched j Code Default Width 10 00 Ft Symbol None Center Height 10 00 Ft _ In Atmosphere Rib Height 7 ft gy Auto Calculate P from ArchFactor Excluded from Arch Factor Ss model execution a rent UE Area Perimeter a i Y Auto Calculate Perimeter Length ft V Auto Length Figure 92 Branch Data Dialog Box 90 Each branch can be color coded to visually differentiate between airway types The Branch Code menu allows the user to color code the schematic Each airway type can have an individual color assigned to it or have the color modified by selecting Define Colors from the Preferences menu and then selecting the Branch Code option as shown in Figure 95 and Figure 96 A tet OY Dic Vn ni ji 7 3 oe RN an ya Email HE ES we File GoTo Edit View Zoom Tools Window Help x Parameter sl JA oe SA eo F E Le bo ah a 071 6 1800 Define Colors Quantity Junction Range Velocity Junction Creation Pressure Drop Lette
126. ssesscscescesceess 76 FIGURE 75 ENSURE ALL BRANCHES ARE CONNECTED sa 77 FIGURE 76 1400 TEVEE VNETEC PROS CHEMA TO ds oso TT FIGURE 77 1600 LEVEL VNETPC PRO SCHEMATIC A 78 PIGURE yS 1500 LEVEL Y NETRLE PRO SCHEMA O e decos 78 PIGURE 797 1920 EEVEE VNETPLE PRO SCHEMA TO canoa 78 FIGURE 00 2000 LEVEL V NETLE PRO SCHEMATIC areri rna asta aac esata Sains Gas tena agen Saray eases ena eens 79 FIGURE 81 AUTOCAD SAVE DRAWING AS DIALOG BOX ccscssessessesescsscsecssesecsecscsscsscsecsscsscsecsessceacsacsacsesseeseeseeaees 80 FIGURE S2 VNETRENEWMODELDIALOS BOX ccc recat aioe nar is 81 FIGURE 83 SELECT UNITS DIALOG BOX iran 81 FIGURE SF MODEL INFOR VIA TION Vi 82 FIGURE 65 IMPORTING THE DXF FILE INTO VANETTE os 83 FIGURE 86 LAYER SELECTION DIALOG BOX cece ccccccecccsccccssccusccesccescceusccusccecceusseuscceucceusceusceusceeusceuccecceesceusceuaes 84 FIGURE 87 PLAN VIEW OF IMPORTED SCHEMATIC ccccsccceccceccescccccuccesceucccuccesceucceucsuscessescsessesssenseuscessesseussensees 84 FIGURE 88 BRANCH GROUPS DIALOG BOX occnoccnnocnnoconiconnncnonoconoronaronnncnnnronnrcnnoronoronnrc nn ronronnnc nn ro nano nnncnunccnnrcnuncnnns 85 FIGURE 89 COMPLETED CROSS SECTIONAL VIEW OF SCHEMATIC cccccccscccscccsccucccsccesceucceuccuscesscesceesceuscesseussensees 86 FIGURE 90 ROTATED 5D SCHEMATIC iris 87 FIGURE 91 DRAWING BRANCHES IN SCHEMATIC CROSS SECTION ccccscccsscceccsscescceuccescencsesccescessesceuscenccesceessensees 88 F
127. stalled correctly Congratulations You can now begin using VnetPC Pro ventilation simulation program If the program window does not open but you get a HASP not found x error please verify HASP not found 0 that the HASP device is properly attached to the computer on a USB HASP the red light in the device should be on Now that the program is functioning check the version number by selecting Help gt About VnetPC Pro Then check for updates and patches via Wwww mvsengineering com gt downloads If the patch has a higher version alpha numeric than shows up in the help about information panel then you may download the patch Simply Save Target to your program directory and then extract the replacement exe and dll files to overwrite the existing version in the installation directory Note that if you retain the current program files as a backup you will need to make sure that you manually verify any 11 shortcut associations Windows may retain the shortcuts targeted to the original program files rather than the installation directory If you have any further questions with regard to the installation process or the operation of this or other MVS software please feel free to contact us by telephone 1 559 452 0182 or email support mvsengineering com 3 Data Preparation and Input VnetPC is structured such that the user moves between views or windows where input and output data are locate
128. t and view data Ventilation networks can be entirely developed within the Schematic view and it provides a rapid means of viewing the network results In the Schematic view different parameters may be plotted onto the network using the Preferences menu 4 4 5 1 Preferences Menu The Preferences menu allows the user to select which output parameters are to be shown and how to show them The key features from this menu are listed below 58 Parameter This command allows the user to identify the desired parameter to be displayed on the Schematic The eleven choices are Quantity Velocity Pressure Drop Air Power Loss Operating Cost Contaminant Flow Results Contaminant Concentration Resistance Branch Number Line Plot Dual Parameters Each parameter may be plotted separately for legibility or the user may use the Dual Parameters feature Dual Parameters allows the user to select two types of parameters to be displayed on the Schematic and the user may select the text color for the selected parameters being displayed The user may rapidly change the parameters being displayed on the Schematic using the quick select tool bar shown in Figure 52 Pana aa e A A Figure 50 Parameter Quick Select Tool Bar Dual Parameters The Dual Parameters feature enables users with the ability to display two parameter outputs on the Schematic simultaneously Users can access Dual Parameters on the Schematic view by first selecting P
129. ta Base a Under the File menu select New b Select VnetPC Pro Fan Curve File then select OK 45 Select units then press OK Under the Curve menu select Add Curve Fill out the Fan Curve Dialog Box with the Pressure and Quantity curves points and the Air Density and Frequency for the original curves then press OK Repeat steps a through e to add as many curves as desired Under the File menu select Save As then save the file like any Windows application with fdb file type 3 4 3 2 Importing a fan curve into a model gt 0 209 Insert the fan into the model as described above select the Edit Fan Curve button on under the fan menu in either the Fan Input or Fan Results views Select the Import button Find the Fan Curve Data Base File in the Windows dialog box Hi light the desired fan curve and select the OK button The fan curve will then be transferred into the Fan Curve dialog box In the Fan Curve dialog adjust the Air Density and Frequency to actual mine conditions then press OK 46 3 4 3 3 Saving a fan curve from a model into the Fan Curve Data Base a While in the Fan Data Dialog Box select the Save button b Find the Fan Curve Data Base File in the Windows dialog box c Select the method to add the fan curve to the data base replace hi lighted curve or add to bottom and select the OK button 3 4 3 4 Importin
130. th the push toward maximizing the efficiency of ventilation systems MVS has incorporated a tool as shown in Figure 39 to modify the fan curve with respect to changes in fan rotational speed based upon the supplied frequency Hz of a variable frequency drive VFD When inserting a fan curve into the ventilation model the user can elect to increase the frequency of the drive or decrease the frequency of the drive thus changing the rotational speed for the fan and the fan characteristic curve MVS provides a program called DuctSIM which is designed to assist engineers and planners with the design and modeling of fan and duct systems Users can create fan curve files in the program which can be used in the modeling of the duct systems WnetPC Pro has been modified to import and utilize fan curves created in DuctSIM in a VnetPC model In previous versions a user would have been required to reproduce the fan curve file for the same fan in both VnetPC and DuctSIM With VnetPC Pro users may create a curve in DuctSIM and import it to a fan curve file manager in VnetPC Pro Fan curves are allowed to be converted from DuctSIM to VnetPC Pro but at the current time cannot be converted from VnetPC to DuctSIM The user may save and import fan curves directly from the Fan Curve dialog box within VnetPC by clicking the Save and Import buttons Note that a fan data file must already exist to allow a curve to be saved to it 3 4 3 1 Creating a Fan Curve Da
131. the fan pressure in the Fan Data dialog box should be input 3 4 3 Fan File Manager VnetPC incorporates a data archival program for the development manipulation and storage of fan curves This feature is called the Fan File Manager The Fan File Manager allows the user to generate different fan files each of which can hold many different curves Hence the user may select to have just one fan file for all mine fans or have separate fan files for each fan perhaps with the different curve settings saved for each individual fan The Fan File Manager 1s accessed directly from VnetPC by selecting File Open and choosing a fan file fdb extension Application of the Fan File Manager is recommended when a large number of fans must be entered edited or deleted from the fan database The user may develop a new fan file by selecting File New and choosing VnetPC Pro Fan Curve File as the new file type shown in Figure 37 43 WnetPC Pro File i WnetPC Pro Fan Curve File Figure 35 New Fan Curve File When a new file is opened a screen will appear which allows the user to input a new curve from the Curve menu see Figure 38 Selecting Add Curve or Edit Curve will bring up a fan curve dialog box similar to those shown in Figure 32 and Figure 33 The user should then enter data as described in section 2 11 2 Once the fan points are entered the file should be saved cy VnetPC Pro VnetPC PRO User Manual fdb Fan Curves ES File
132. tins Outpt Dalasan osc a 66 4 4 9 DXE PIS GEO iaa 66 4 3 CHANGING THE APPEARANCE OFA TABLE VIEW as 66 O WINDOW MENO blade 68 TUTORIAL aaaea ESELA ENAA ENA NOATE veueescccotdecsareseaseseiveuutsecssosdcsuseruetesentwousiwensetss 70 Ii TINT ROD CEO Nes esia arao ti id 70 32 SETTING UP THE MODELIN AUTOCA Dinar A 70 32l Adding the AV entilation Layers ardillas dios 71 3 22 Drawing the Schematic Line Diagram occccccncnccnnonnnnnnonnnnnnnnnnnnnnnnnnonononnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnss 12 5 2 3 Ee KOU OS DAF Tlatelolco 79 5 3 WORKING IN THE VNEFPC PROGRAM icscssacvswnasieesddtivacvnnomosudaadiivacesnsismnnadedoadunpasataloadsstcsennwsapdaddboadeadweasedendtosdens 80 5 3 1 Setting Up the V net PC Plena od a N a 80 532 SCHEIMAUIO VIS A aN a alcoi 82 5 3 2 1 opor mo the chema oil O calido 83 5 3 2 2 Defne Croup AHON Seasann A A A ido 85 5 3 2 3 Viewine and Edito the Schematic 10 o Done ias 87 5 4 ADDING BRANCHES TO THE SCHEMATIC occcccnnocccnnnnnnoconnnnnorocnnononoconnnnnnnornnnnnnnoonnnnnnnocnnnnnnnocnnnnnnnocnnnnnnnonnnnnnnnos 87 5 5 DEFINING BRANCH ATTRIBUTES RESISTANCES cccccsecccssccccsscceseccesecsescceesecseesseesseessseeusseesseeseseeeeseeenss 90 5 6 INSERTING FANS AND FIXED QUANTITIES ccccccccsseccccsscccceseccccsececeueccceusecsecusecseuueceseeseceseueceseeuecessueeseeeuess 93 IE GXDDING AC ONTAMINAN F x2 4 5 254 cyitesca cara A A agua oe eas 95 5 0 PROGRAM EXECUTION e do abu eae oie a 95 A
133. twork The range of fan duties required airflows pressure drops operating costs and the location of ventilation controls may be ascertained for the entire life of a project by conducting time phase exercises Options within VnetPC allow for the display of parameters and manipulation of three dimensional networks production of lists from input and output files and plots of the schematic input data and output data 2 2 Background Theory of VnetPC The VnetPC program has been developed with the assumption of incompressible flow and is based on Kirchhoff s Laws The code utilizes an accelerated form of the Hardy Cross iterative technique to converge to a solution 2 3 List of Main Program Features Full color interactive 3D network schematic Enhanced expandable coordinate system Data input and output via the Schematic or tabular views Color coding of branches for airway type user defined Import DXF files from CAD and mine planning programs Ability to enter series and parallel arrangements for fans Imperial and SI units with full data conversion Automatic allocation of surface branches to close meshes around surface nodes Notepad to enter detailed description of simulation Full annotation capabilities in all schematic views allows angled text Automatic calculation of branch length from coordinate values Regulator orifice sizing tool Default network size limit is 10 000 branches 4 000 junctions and 600 fans Extensive Help Too
134. unique preferably new layer with an obvious name such as VnetPC The end point for each line or section of a polyline should represent a node location Care must be taken to ensure that the end and starting points of connected branches are at exactly the same coordinate 1 e the nodes do actually connect This would be done in AutoCAD using the snap to lt endpoint of gt or lt intersection of gt options Failure to do this will result in the data being imported as separate lines rather than a network The DXF import feature 1s not limited to CAD programs and will support DXF data from most mine planning software Care needs to be taken to ensure that a level is contained in the DXF file which represents the simplified schematic If the mine plan is not simplified and centerline coordinates are imported for all the lines and polylines then an extremely large network will result for example a coal mine could import every crosscut in the mine The resulting network may be unworkable 3 3 4 5 Surface State In previous versions of VnetPC the user was required to manually connect all the surface nodes together using zero resistance dummy branches to ensure full mesh closure This is not required in VnetPC Pro The user can now select the surface state of a branch during data entry by checking the box labeled In Atmosphere Previous versions of VnetPC also required that 37 the user always categorize the surface branch as either
135. ut will not apply it to the system To add a shock loss resistance to the model with the Branch Data dialog box the user must check the box labeled Shock Resistance Users then may manually add a value to the Shock Resistance text box or select Calc Shock Loss to calculate a shock loss resistance In order for VnetPC Pro to calculate the shock loss resistance users must define three parameters airway cross sectional area average mine air density and Shock Loss Factor The cross sectional area is user defined for each branch in the Branch Data dialog box or the Branch Input view The area may be either input manually or calculated based on the profile type dimensions directly above the area cell in the Branch Data dialog box To calculate the area from the cross sectional area dimensions the user will need to check the box labeled Area Perimeter Auto Calculate If the user changes the cross sectional area after calculating the Shock Resistance the user must select Calc Shock Loss again to recalculate the shock loss or manually override the shock loss as this number will not update with changes to the model The average mine air density is user defined on the Model Information view After the user selects Calc Shock Loss the Shock Loss Factor dialog box will be displayed see Figure 12 Shock loss X factors may be defined as the number of velocity heads that give the frictional pressure loss due to turbulence at any bend v
136. utes shown and make any wanted changes In VnetPC often a RAMP group is created to include all branches that identify a mine ramp connecting multiple levels in the mine This usually provides the user a little more challenge in that it is not a level rather it is a group that spans a wide range of mine levels For this reason the ramp is often created within VnetPC by connecting the different levels with a single line representing a section of ramp between two points rather than having to specify elevations for multiple broken sections of ramp However if you choose to create a 3D ramp in AutoCAD or other CAD program to be follow the exact path of the ramp the z coordinate values will be automatically imported with the rest of your model If the ramp was created in 2D the elevations for the nodes in the RAMP group can be entered in either one of two ways In the sectional views existing nodes can be moved anywhere in the vertical or horizontal planes with the mouse or each node can be selected individually and an elevation assigned to it Individual nodes can also be selected and an elevation assigned to them in the isometric view The junction is edited using the Edit icon 4 located on the Toolbar or by selecting Tools gt Edit and then clicking on the junction Right clicking with the pointer 85 will also allow editing through a drop down menu by selecting Junction Data The Edit Junction dialog box will ap
137. wed using the Branch Results Fan Results Fixed Quantities Schematic and Contaminants views The output data can also be sent from each view to a Plotter or Printer Any computational errors are automatically listed in the Error List dialog box immediately following execution This dialog box may also be accessed from the Tools menu in any view 4 4 1 List Errors VnetPC identifies four basic execution errors Three of the errors appear below in Figure 49 Error List Total Number of Errors 3 Errors Too many fed quantites Branch from 30 to 33 No mesh found for branch Branch from 10 to 20 No mesh found for branch Branch from 0 to 22 Branch omitted in mesh selection Branch from 10 to 20 Branch omitted in mesh selection Branch from 20 to 22 Branch omitted in mesh selection Branch from 22 to 63 Branch omitted in mesh selection Branch from 92 to 50 Branch omitted in mesh selection Branch from 0 to 94 Branch omitted in mesh selection Branch from 83 to 95 Locate in Schematic Figure 47 View Errors Dialog Box Once an error has been identified in a branch the program does not stop the execution but continues operation until 1t converges on a solution The following errors may occur 55 4 4 1 1 Too Many Fixed Quantities This error message arises 1f the input data file contains an excessive number of fixed quantities or inject reject branches If fixed quantity branches are used excessively in inte
138. y 0 01399 0 01664 75 5 89 7 Single Smooth Lined Drift 0 00440 0 00560 23 7 30 2 Bored Raise 0 00466 0 00698 25 1 37 6 Alimak Raise 0 01126 0 01579 60 7 85 1 The SI friction factors are given in kg m 3 the imperial friction factors are given in Ibf min 2 ft 4 x 10210 104 Note Mine Ventilation Services Inc does not make any representations as to the correctness of the provided k Factor data This data should be used only for initial planning purposes and every effort should be made to accurately measure the actual friction factors and resistances encountered at the mine 7 1 5 R L Factors The VnetPC Pro program can utilize standard resistance per length data to calculate airway resistance throughout the ventilation network It has been established that when modeling bedded deposits where entries are kept fairly uniform resistance per unit length data can be successfully used The following charts and figures based upon measured field data help the user identify the most appropriate friction data 7 1 5 1 Resistance per Length for Tailgates This graph shows tailgate resistances measured at several mines and can be used for initial ventilation planning However no two tailgate entries will deteriorate and act in the same manner so these resistances must be field verified when available These resistances are based upon two rows of 1 2 m wide cribs placed on 2 4 m centers In order to provide an estimate for the average resistance

VnetPC Pro Users Manual and Tutorial

Contents

Download Pdf Manuals

Related Search

Related Contents