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GLHEPro User Manual - Building & Environmental Thermal Systems

1. eene 35 22 IU D 35 22 11 Write Current Input Data to File 35 2 2 12 Read Input Data trom Pile ttes see eid trek ter ure dau 36 2213 4 TANS AS Default euo tees eda 36 HONEC MEI A DIM E 36 2279 perdent edition cst 36 224 2 View Output Elle etus een tU as Pe a e E 37 DDD gt m 37 uL 37 224 1 Read Heat Pump Loads From a File iiec ete tod agin 37 2 2 4 2 Bait Heat Pump Monthly 0 45 eite tht t otto ette 39 22 3 EdiUGEHE Monthly LOBOS Eo te doen po devas as 41 PER REM Dii c 4 2 2 6 42 2201 TUR GEHESIM Em 42 22 02 512 wes 45 2429 Perform Hybrid GSHP SIZING aM eia Ren 46 22 Welpoansspsatep RD iR ad RG UD aes 47 DDB Adde NOES eq oie na ee diataped odo 47 2 3 GLHEBPro UE Rea INR eara aU ve RET 48 2 JOGDBHBPro Error Wiessabes sah ei Uer 52 3 Program Improvements eeno a
2. Figure 2 32 The GLHESim control sheet You may wish to start a simulation in a month besides January for a case where the building comes online in a different month In that case enter the month number e g for September enter month 9 In no case should you enter a number greater than 12 for the starting month When you have entered the correct months click OK and GLHEPro for Windows will run the simulation The length of time required to run the simulation is related to the number of months that are being simulated and the processing power of the user s computer While GLHEPro for Windows is running the simulation it is also creating an output file which contains all of your input data along with the monthly heat extraction rate per unit length of borehole the monthly power required by the heat pump and the average exit and inlet fluid temperatures minimum and maximum peak inlet fluid temperatures in the boreholes for each month as specified in the Output File Preferences The output file will be located in the directory where the input file Section 2 2 1 1 has been read If you have not read or saved any input file it will be located in the directory in which the default file for GLHEPro for Windows has been installed Alternatively specifying the path name in the Send Output data to file text box allows the user to determine precisely where the output file will be located Clicking on the File Preferences
3. 1 Eile Edit Insert Format Tools Data Window Help Adobe PDF a 5 SRY Bee LS 4 i 75 BL 7 10 BZU 9 95 5 A AB27 Y F G H J K N o a R 5 U Y v 59 332002800 4945493 0 60 v3 2002 10 00 2218758 114 0788 pr G 1322002 1100 1499799 42302 31 Heating Day Temperature Response Cooling Day Temperature Response 62 00021200 104864 124723 4 263 11320021200 90465 19 202981 iw 1200 64 32002 400 64219 93 250606 4 65 20021500 52543 74 275417 2 66 W3 20021600 59749 14 2719844 1000 1000 67 20021700 7979298 174946 2 68 20021800 123078 2 4077122 63 10120021900 0 0 0800 0800 70 103020022000 0 0 Hourly Response Hourly Response 1212002200 0 0 TM Duration thr avg L Duration 2 hr aug Mg 202220 0 Duration 2 hr ava Hi Duration 3 hr avg 73 103120022200 0 0 5 5 H 42002 0 0 Duration 3 hr avg Duration 4 hr avg 75 vsi2002 4000 0 0400 76 42002200 0 0 7 342002300 M66006 0 0390 78 42002 4 00 985211 0 79 1992002500 1887088 0 80 18442002600 3913032 0 0 000 0 000 81 42002 7 00 5726959 0 0 4 M M 20 AM 0 82 1442002 8 00 1606751 83 1412002800 515538 o Hour 94 14920021000 2372524 9006 77 85 18420021100 1666217 5762527 86 14 20021200 1376948 129403 87 1442002 1300 1139408 2107408 Monthly Loads 88 412002 14 00 4899187 2506257 89 1402002
4. an ni e Saina 54 Addit nst Version rr D 54 3 22 Additions to D Bala gera aes Breves 54 56 APPENDIX Custom Heat pump Curve 58 ERAN Cc te a iocos pem seam ducas tato Ductus 61 Enter Coolina Loads yh IU 63 Exiter Heating usen uou ou Hp tibt aaa e ipit 64 View Heat Pump COoeffIele RI unos NS UR Reate Dui an 65 View Heat Pump Curve EIUS oos ote diese TRIS IMs aca ndun s Quos ko Guo FU E MS 66 APPENDIX B Interfacing GLHEPro for Windows essere eene enne 72 APPENDIX C Information on New Heat entente enne enne 74 76 APPENDIX D More on Undisturbed Ground TI APPENDIX E Peak Load Duration Tool estes treten eren ties Inno edis een avo 80 Peak Load Analysis T6001 et EI ORAE 8l TOG OM ER NP D 8l 1 Load ecrit d esae s cH v he net see eta tes es
5. 26 p Ground Temperature Selection Zi All ground temperatures on this are in Temperature Selected Figure 2 16a Select Ground Temperature dialog box Ground Temperature Selection Non U S Beijing China Changchun China Changsha China Chengdu China Guangzhou China Caution The approximation used to obtain ground temperature from air temperature may not be good for your location See Section 2 1 4 of the manual Figure 2 16b Non U S Ground Temperature dialog box 27 2 1 5 Select Fluid Properties As with ground properties GLHEPro for Windows offers the user a method to enter the physical and thermal properties of the circulating fluid that will be used in the system If the fluid properties are known the data must be added to the fluid library as a new fluid To change the fluid displayed on the GLHEPro Dialog click the Select Fluid button The next dialog box that will appear is the Select Antifreeze Mixture dialog box seen in Figure 2 17 In this dialog box the user may select one of several fluid types from the drop down list a fluid concentration as well as the mean fluid temperature may also be specified Note that this mean temperature will be used solely to calculate the fluid properties and has no other bearing on the simulations For sizing calculations it is recommended that the mean fluid temperature be set to the limiting heat pump entering fluid temperatur
6. AS Two tubes spaced 1 8 apart at the center of the borehole B Two tubes equally spaced between the borehole edges Both tubes placed against outer edge of borehole For a double U tube configuration the four configurations are for convenience given the same naming scheme as for a single U tube configuration However it should be recognized that these spacing configurations are only analogous to those for the single U tube configuration The four configurations are as shown in Figure 2 5b 0 Each tube is touching the adjacent two tubes 14 AS Similar to configuration AO but each tube is moved 1 16 3 mm towards the outside of the borehole B Tubes are equally spaced between the borehole edges however if due to the size of the tubes this would cause interference the average of configurations AS and C is used C All tubes placed against outer edge of borehole For design purposes either configuration AS or B the default is recommended Configuration AS would be somewhat conservative Configuration C would be difficult or impossible to achieve in practice without some type of spacing system that would press the tubes to the outer edge of the borehole To modify the shank spacing single click the Set button next to the shank spacing text box Click the radio button corresponding to the desired configuration and then click Accept to return to the G function and Borehole Resistance Calculator dialo
7. Figure E0 7 Albuquerque office building peak heating loads Cooling Load Profile a 79 Figure 0 8 Albuquerque office building peak cooling loads 89 The problem we are trying to solve is to find an equivalent approximation for the peak day loads that can be represented for each case as a single value of the load at a given duration This looks like a square wave as shown in Figure 0 9 In this case we are approximating the actual load as a value of 2491 kBtu hr over three hours as compared to a single hour peak value of 2690 kBtu hr Cooling Load Profile 3000000 2500000 2000000 1500000 1000000 Cooling Load Btu h 500000 Figure E0 9 Albuquerque office building peak cooling loads with single load duration superimposed The Peak Load Analysis Tool allows us to check the normalized temperature responses for three peak load durations and one of two peak load calculation methods at a time This has been done using the average over duration peak load calculation method for 2 3 and 4 hour durations and the results are plotted in Figure E10 The normalized temperature response for the actual hourly loads is shown as a heavy black line and by definition it peaks at a value of one The 2 3 and 4 hour durations are shown in color The 3 and 4 hour average durations both appear to have a maximum response of almost one Zooming in on that
8. Notes box will result in a Notes file file name as given extension NTS this file will contain the project name and any notes the user has entered about the project See Section 2 2 8 for details about adding notes to a project Checking the box to create a CSV file will do precisely that This CSV file will have the same name as that provided for the output file and will consist of a comma separated list containing the monthly temperature summary for further processing by the user The CSV file can be brought directly into Excel and plotted 2 4 GLHEPro Error Messages There are a series of error messages that you may encounter during the operation of GLHEPro These messages are usually indicative of an error in user inputs issues with convergence or a registration problem Most of the messages are self explanatory more information is provided for a few of the more complex errors If you encounter an unhandled error or bug in the program you can report it to GLHEPro Technical Support for contact information see section 1 5 Invalid Registration appears after the splash screen while opening GLHEPro This message indicates that the program is unregistered has lost its registration or is a demo copy Registration Error 1 The registration code you input is not valid for your computer Make sure that the program is installed on the computer whose serial number was registered on the online form If you need to re register you
9. box will cause the dialog box shown in Figure 2 33 to appear This box allows the user to specify which parameters the simulation will write to a file The simulation outputs will be covered in more detail in section 2 3 43 When the simulation is complete a Glhepro Results dialog box will appear that will provide a very brief summary of the results The information in this screen includes a description of the borehole configuration the active borehole depth the total borehole length and the minimum and maximum temperatures entering the boreholes and at what months they occur Figure 2 34 shows the Glhepro Results dialog box When finished with the Glhepro Results dialog box click to return to the Glhepro Dialog Box Output File Preferences Select Output File Preferences E Create Notes NTS Create Microsoft Excel Readable CSV Monthly Loads Heat Pump Monthly Loads E Temperature Summary E Monthly Temperatures Figure 2 33 The Output File Preferences dialog box If the specified borehole spacing to borehole depth ratio called the B H ratio or simply B H exceeds the range of such values catalogued for use in computing the g function the results WILL be extrapolated and the user will be warned that the B H ratio exceeds the bounds in either direction of the available data For most borehole configurations the g functions are tabulated for B H between 0 02
10. 1 3 3 Peak Load Method Average over duration Maximum during duration Cancel OK Figure E0 4 Primary input form 86 r Control Sheet Secondary Parameters System Sizing U Tube Size Borehole Depth Ft 164 05 Inner Diameter fin 0 858266 Borehole Radius in 2 16546 Outer Diameter in 1 051179 Thermal Conductivities Volumetric Heat Capacities Pere 02250115 2299122 Grout Btu hr ft r 0 42998211 Grout ptu t s r 58 16391 Ground Btu hr ft r 20202169 Ground Btu ft 3 r 32 2056 Fluid Btu ft 3 F 62 21943 Convection Coefficient Btu hr ft 2 F 2014 584 Borehole Thermal Resistance hr ft F Btu 0 357971265 Figure E0 5 Secondary input form 4 Determination of Peaks The Peak Load Analysis Tool calculates the response of the ground heat exchanger in the form of normalized temperature response This normalized temperature is the ratio between the calculated temperature difference and the maximum temperature difference of the full hourly load profile The temperatures are normalized in this way to avoid requiring a much broader set of input data e g monthly loads number of years ground temperature etc For determination of the peak load duration the magnitudes of the temperatures themselves are not as important as the temperature changes To calculate the normalized temperature response for any partic
11. 0 2 and 0 4 for the load ratio and 0 01 and 0 05 for the step sizes At present no advice can be given as to how to choose initial guesses that will produce results The results of a sample HGSHP sizing are shown in Figure 2 36 The data shown in the results window are similar to those from a standard GSHP simulation with the addition of the capacity of the supplemental device either heat extractor or heat rejector Rf GLHEPRO Results Borehole Information Borehole Configuration LINE CONFIGURATION 3 1 x 3 line Each Borehole Depth 426 74 ft Total Borehole Depth 1280 22 ft Distance between borehole centers 15 00 ft Average Temperature Maximum Average Temperature 72 70 F atMonth 92 Minimum Average Temperature 43 99 F atMonth 1 Peak Temperature Maximum Peak Temperature 90 00 F at Month Minimum Peak Temperature 20 00 F at Month Supplemental Device Information Supplemental heat rejector capacity 8 8 kBtu h Figure 2 36 Results of a HGSHP sizing 46 Finally it should be noted that as of GLHEPro V4 0 this procedure is experimental in nature Although we have obtained very good results for a number of cases it sometimes fails to converge or converges to an obviously wrong answer Examples of obviously wrong answers include designs with GLHE that are longer than those of a standard GSHP system designs where the user specified heat pump EFT limits are either exceeded or never approached User
12. 10212002 16 00 10212002 17 00 10212002 18 00 10212002 19 00 12 2002 20 00 1212002 2100 10212002 22 00 10212002 23 00 1312002 3 2002 100 13 2002 2 00 1312002 3 00 13 2002 4 00 13 2002 5 00 1342002 6 00 43 2002 7 00 13 2002 8 00 B Heating required kw 0 oooocooococoocooccoocoocoococococ 9 0 033501 540 2764 357 0159 223 8159 114268 58 393 22 90966 7 731542 3 016087 3 89053 8 360838 2409844 0 0 361107 403 3048 Cooling required kw 0 ooooocoocoococooocooocoococooocococooocooco 0 1092673 5 325284 0 264329 2 9 9 0 9 9 o 9 9 2 9 9 2 0 9 F RN J AMEN N o P 1 9 5 Y Location BOK Office Building Albuquerque Unit System S Meric 50 English IP Compute Pesk Days Launch Input Form Please wait a moment after switching units Instructions Form below can also be usedto get daily peak response profiles Press the Compute Peak Dags button to find days of mazimum loads Heating Peak Duration 1 1 Use the input form to select peak load durations and peak determination method Heating Peak Duration 2 2 Average over duration Determines the highest average value for Heating Peak Duration 3 3 the peak day over the peak duration and uses this value throughout the peak duration Cooling Peak Duration 1 2 Maximum during duration Determines the absolute
13. 32 62 31 62 23 0 343 2 42333 FreezingPoint Density Conductivity Viscosity Heat Pump Heat Pump Selected ClimateMaster Classic Model 030 Select Heat Pump Figure 2 1 Glhepro Dialog Box SS esentative borehole H is the active borehole depth D is the insulated upper portion and is the borehole radius The Active Borehole Depth ft or m default 150 ft The borehole length over which heat transfer takes place H as shown in Figure 2 2 It is sometimes the case that the upper region of the ground has a lower conductivity than the deeper part of the ground due to being dryer The cautious designer may wish to treat part of the borehole distance D as being thermally insulated in order not to over predict the ground loop heat exchanger perfo ilson 1987 To run a simulation using GLHESIM see Section 2 2 6 1 the Active Borehole Depth must be specified by the user If the borehole depth is not known it may be determined using GLHESIZE see Section 2 2 6 2 In this case the entry for the Active Borehole Depth is ignored e Borehole Diameter in or mm default 4 33 in The borehole diameter 2r see Figure 2 3 is the diameter of the borehole that will house a heat exchanger loop If a borehole casing is being used then is the outer radius of the casing If no casing is being used then can be estimated as the radius of the drilled borehole which will house the two legs of the heat exch
14. Heat Pump Curve Fits Cooling Heat of Rejection QC a b EFT c EFT 2 kBtu hr Power d e EFT f EFT 2 1 250726 d 0 063444 0 003577 0 000688 0 000059 0 000015 Heating Heat of Absorption QH u v EFT w EFT 2 kBtu hr Power QH x y EFT z EFT 2 u 0 427715 X 0 110967 V 0 008164 Y 0 000684 w 0 000053 z 0 000003 QC Cooling load kBtu hr QH Heating load kBtu hr EFT Fluid temperature entering the Heat pump F Figure A 6 The twelve curve fit coefficients for a quadratic curve fit for the performance data in Figure A 2 View Heat Pump Curve Fits We can also view the curve fits by selecting one type of curve four options 1 Heat of Rejection QC vs Temp 2 Power QC vs Temp 3 Heat of Absorption QH vs Temp 4 Power OH vs Temp that we wish to see and clicking View Curve to view that curve figure A 7 shows the curve fit for Heat of Rejection QC vs Temp from the Add Heat Pump dialog box Click CLOSE to return back to Add Heat Pump dialog box 66 a Curve Correlation Plot Heat of Rejection QC vs Temperature 60 80 Temperature F Figure A 7 Heat pump curve fit for Heat of Rejection QC vs Temperature Now let s determine the coefficients for a linear curve fit Click Add Heat Pump as described above in the section Customizing Heat Pump Change the desired type of curve fit from Quadratic to Linear All of the performance
15. This scrolling list contains all the fluid types from the user library After entering the desired values click to confirm the selection of this fluid Add Fluid Properties Fluid Type Weight Mean Temp Freezing Point Density Volumetric Heat Viscosi Thermal Conductivity Ip ft 3 Btu F ft 3 Ibm ft h Btu h ft F Figure 2 19 Add Fluid Properties dialog box 29 During input the values of all the properties are validated Permissible values of various properties are as follows Table 2 2 Range of permissible values for various properties of user s fluid type Mean Temperature _ 100 F lower limit 73 33 C lower limit Freezing point 100 107 37 F 73 33 41 87 C i Ib Volumetric Heat 14 91 149 1 5 1000 10 000 Capacity p Thermal Conductivity 5 78E 11 577 8 Btu h fi F Each fluid mixture type is uniquely identified by its description and weight percent So no two records can have the same description and weight percent The user will not be permitted to enter a fluid type with the same description as any one of the fluid types from the standard library If the user enters a record with the same description and weight percent as any one of the fluid type records from the user library he will be asked to overwrite the existing one The user can also modify fluid type records that exist in the user library To use t
16. and Delete push buttons are disabled when the soil selected is from the standard library Additionally the user can also search for soil types that match specific criteria by clicking the Search button Figure 2 13 shows the dialog box that will appear The user can specify the values for various properties All matching soils from both the standard and the user libraries will be displayed in the ensuing table of results Searching for a particular description will return all soil types that have descriptions beginning with what was entered into the search box After a search the user can revert to displaying all the soil types by clicking the Show All button which is enabled only when search results are displayed The user cannot add modify or delete any soil types while search results are being displayed the buttons corresponding to those actions will be disabled at that time 23 Search Soil Description Conductivity Wi m K Densty 5 7 Kg m 3 Specific Heat _ kJ Kg K Volumetric Heat kJ K m 3 Figure 2 13 Search Soil Properties Dialog box Users might desire to share soil types of common interest This can be accomplished by making use of the import and export features incorporated within the Ground Properties dialog box To use the export feature click on the Export button on the Ground Properties dialog box Figure 2 14 shows the Save As dialog box that will appear Enter t
17. pp 297 304 Witte H J L G J van Gelder J D Spitler 2002 In Situ Measurement of Ground Thermal Conductivity The Dutch Perspective ASHRAE Transactions 108 1 263 272 Yeung D 1996 Enhancement to a Ground Loop Heat Exchanger Program Masters thesis Oklahoma State University Stillwater Oklahoma Also available at http www hvac okstate edu pdfs Y eung pdf Young T 2004 Development Verification and Design Analysis of the Borehole Fluid Thermal Mass Model for Approximating Short Term Borehole Thermal Response M S thesis Oklahoma State University Stillwater Oklahoma Also available at http www hvac okstate edu research Documents Rays Thesis pdf 57 APPENDIX A CUSTOM HEAT PUMP CURVE FITS 58 GLHEPro for Windows requires four heat pump curve fit equations to describe the performance of the heat pump For the cooling mode Heat rejection rate divided by the cooling rate and Power required by the heat pump divided by the cooling rate For the heating mode Heat extraction rate divided by the heating rate and Power required by the heat pump divided by the heating rate Or more specifically the following equations are used see Section 2 1 6 for the Heat Pump Curve Fits dialog box For the cooling mode Heat Rejection Rate QC a b EFT EFT Power QC d e EFT For the heating mode Heat Extraction Rate QH u v EFT w EFT Power QH x y EFT 2
18. 3 937 in 2 Volumetric Flow Rate borehole 10 5468 gal min Fluid Factor 1 Unitless multiply fluid in the system by this amount Volumetric Heat Capacities Thermal Conductivities Soil 32 21 Btu F ft 3 Soil 1 Btu hr ft F Grout 58 1664 Btu F ft 3 Grout 0 43 Btu hr ft F InnerPipe 229922 Btu F ft 3 InnerPipe 0225 Btu hr ft F OuterPipe 229922 Btu F ft 3 OuterPipe 0225 Btu hr ft F Convective Coefficients Convection Coefficient at Inside of Inner Pipe 244 4523 Btu hr ft 2 F Convection Coefficient at Outside of Inner Pipe 12 1099 Btu hr ft 2 F Figure 2 4e Borehole resistance calculator concentric tube The following is a list with brief descriptions of the parameters contained within the G Function and Borehole Resistance Calculator sheets The Borehole Diameter in or mm default 2 4 33 in The borehole diameter is twice the borehole radius that was entered in the main form Changing either value will also automatically change the other The Shank Spacing in or mm default 0 744 in Single and double U tube configurations only The shank spacing is defined as the distance between the outer circumference of the U tube Paul 1996 defined four different spacing configurations Users may select one of the four spacing options or enter other values For a single U tube configuration the four predefined configurations are as shown in Figure 2 5a A0 Two tubes touching in the center of the borehole
19. Cancel will return you to the main window without preserving any modifications 18 2 1 2 Select Borehole Configuration This option is used to select a borehole configuration from a list of approximately 307 different configurations available with the GLHEPro for Windows software The borehole configuration simply describes the pattern of the boreholes at the surface of the ground for example 15 boreholes in a5 borehole by 3 borehole grid To view the possible borehole configurations click the Select Borehole push button using the mouse Figure 2 8a below shows the Select Borehole Configuration Dialog Box Select Borehole Configuration Select Configuration LINE CONFIGURATION Select sub configuration 3 13 line Figure 2 8a The Select Borehole Configuration dialog box This dialog box provides a list of the 7 different top level configurations Once you have decided a borehole configuration click the Select sub configuration drop down box to choose the number of boreholes needed for that configuration as shown in Figure 2 8b Each configuration has a different subset of available selections The Single Configuration is just a single borehole while the Line Configuration is just a line Figure 2 9 shows examples of the other five configurations The L2 configuration is just two L s with the outer dimensions given The Open Rectangular Configuration is a rectangle
20. and 0 5 For 250 deep boreholes this would mean that any spacing between 5 and 1257 is acceptable from a calculation standpoint even though it may not be physically feasible Rf GLHEPRO Results Borehole Information Borehole Configuration LINE CONFIGURATION 3 1 x 3 line Each Borehole Depth 150 00 ft Total Borehole Depth 450 00 ft Distance between borehole centers 15 00 ft Average Temperature Maximum Average Temperature 109 10 F atMonth 92 Minimum Average Temperature 17 21 F atMonth 1 Peak Temperature Maximum Peak Temperature 206 88 F at Month Minimum Peak Temperature 34 79 F at Month Figure 2 34 The Glhepro Results dialog box after GLHEPro for Windows has completed a simulation run 44 2 2 6 2 Run GLHESize This option is used to determine the required active borehole depth H to meet a desired maximum or minimum fluid temperature entering the heat pump To use GLHESize choose the Perform Sizing option from the Action Menu The GLHESize Control Sheet appears and is shown in Figure 2 35 GLHESize Control Sheet Temperature Limits Maximum Fluid temperature entering the heat pump 90 Minimum Fluid temperature entering the heat pump 20 Duration of Sizing First month of simulation 1 Last month of simulation 100 Send output data to file glhewin glo File Preferences ome Figure 2 35 The GLHESize control sheet GLHEPro for Windows determines the require
21. configurations The demo version only allows the basic 1 3 16 and 64 boreholes Option 120 allows up to 120 boreholes arranged in lines L shaped fields U shaped fields open rectangular and rectangular fields The LRO option enables rectangular boreholes with greater than 100 boreholes All features in the 120 and LRO options are enabled in the 400 version In order to unlock those features the user must first obtain a serial number From the Register menu choose Show Serial Number An example result is shown in Figure 1 2 The serial number Your serial number is 12345 to Clipboard Figure 1 2 Example serial number After obtaining the serial number press the Copy to Clipboard button to copy the serial number to the clipboard Also you will need to know your CD distribution number License Number given on the CD or in the email with the link to your download Then either Register online at http www hvac okstate edu glhepro on the registration page This is the preferred method E mail your contact information along with the serial number CD number to glhepro G okstate edu Regardless of the means with which you contact us we will endeavor to get back to you within one working day If you fail to hear from us within one working day and this poses an immediate inconvenience please follow the second option above and note in your email that you ve
22. data that you previously entered has not been erased therefore you can now view the coefficients and the curve fits The results for this linear curve fit are shown in Figure A 8 Figure A 9 through A 12 show comparisons between the linear and quadratic curve fits for each of the four curve fit equations Also shown on these plots is the actual data from the performance data given in Figure A 2 67 Cooling Heat of Rejection QC a b EFT c EFT 2 kBtu hr Power 4 e EFT f EFT 2 Heating Heat of Absorption QH u v EFT w EFT 2 kBtu hr Power QH x y EFT z EFT 2 v w pom gt QC Cooling load kBtu hr QH Heating load kBtu hr EFT Fluid temperature entering the Heat pump F Ca Figure A 8 The twelve curve fit coefficients for a linear curve fit for the performance data in Figure 2 68 Linear Fit Quadratic Fit Performance Data o o o o 5 2 tc o 45 50 55 60 65 70 75 80 85 90 95 100 Temperature F Figure A 9 A comparison of the linear and quadratic curve fits for the Heat of Rejection vs Total Cooling equation Linear Fit Quadratic Fit Performance Data Power Total Cooling 60 65 70 75 80 85 90 95 100 Temperature Figure A 10 A comparison of the linear and quadratic curve fits for the Cooling Power vs Total Cooling equation 69 Line
23. for the specific borehole configuration used the convection coefficient is different for single double and concentric boreholes When using GLHEPro to compute the convection coefficient if the flow in the tubes is turbulent the convective coefficient is calculated with Gnielinski s correlation 1976 When the flow in tubes is laminar it is simplified as a constant heat flux problem which gives an analytical solution of Nu 4 364 If transition is assumed to occur at Reynolds number of 2300 a sudden jump in the value of the convection coefficient will occur The default is correct for the default borehole configuration default flow 17 When the Reynolds number is in the transition region between 2100 and 2500 the Nusselt number is determined via linear interpolation between 4 364 at Re 2100 and the value given by Gnielinski at Re 2500 The Reynolds number is computed using the user specified flow rate and inner pipe diameter Viscosity density and Prandtl number are based on the user defined assumed average temperature The Reynolds number is displayed for reference as shown on Figures 2 4a and 2 4b When using the second option to calculate the convection coefficient the user can change the working fluid type average temperature and fluid concentration by clicking the Select Fluid button For more details on this see Section 2 1 5 The Select G func Print Version Dialog Box as shown in Figure 2 7 GLHEPro can also pr
24. mouse to set the cursor in the box where you want to edit the loads If no peak loads are defined for either heating or cooling enter 0 in the appropriate boxes Peak load duration Hours at Peak may be set to zero if you do not want to use peak loads When you have entered edited all of the cooling and heating loads click OK to confirm the edited loads or Cancel to exit without editing the loads The Clear Loads option is used to clear the monthly total and peak loads These loads will be set to zero Users can also copy to or paste the monthly total and peak loads from an Excel worksheet or any other application which arranges the loads in tabular format In order to the loads press the button the loads may then be pasted in a tabular format into an Excel Worksheet or other document In order to paste loads from an Excel worksheet into the Edit Heat Pump Loads dialog box after copying that data to the Clipboard the user should simply click the Paste button If problems arise in copying the data to the table click the Clear button and try again Regarding the duration of the peak loads the use of a peak pulse specified as a peak load with a user specified duration is a simplification of the real problem where the load changes continuously The appropriate duration depends strongly on the building peak load profile Two examples from Thomas Young s M S thesis Young 2004 are shown below The firs
25. option from the File menu a Save As dialog box will appear Type the name of the file where you want current input data stored in the File name box You may also change the file type folder and drives Once the filename is entered correctly click the Save button to confirm the file location Select Cancel to exit without saving the input data file GLHEPro for Windows will write all of the input data to the file that you specified and then return to the Glhepro dialog box If you desire to examine the data file or wish to simply have a hard copy of all of the input data in an easy to understand format you may open this file with a text editor e g Notepad and print it If you do open the file take care not to alter the format of any data line GLHEPro for Windows requires a specific format for this file in order to read the input data at a later time see Section 2 2 1 2 35 2 2 1 2 Read Input Data from File With this option you are able to read the input data that you have saved earlier To read the input data from a file choose the Open option from the File menu This dialog box requires you to select the name of the file that contains the data that you want to read into GLHEPro for Windows the same way as you read the loads file Once the filename is entered correctly click Open to read the data and update all of the parameters or click Cancel to exit without reading the input data file GLHEPro for
26. or injection capacity allows for a smaller ground loop length in systems that are dominated by heating or cooling GLHEPro can size both the ground loop and the supplemental device Selection of this option will bring up a control sheet identical to the GLHESize control sheet Figure 2 35 except with a check box output option near the bottom to write HVACSim input file The HGSHP sizing procedure is basically an optimization algorithm that attempts to adjust the length of the GLHE and the size of the supplemental heating or cooling device in order to just hit both user specified temperature limits over the course of the system operation As such the HGSHP procedure may take a few minutes to run depending on the chosen simulation duration Additionally due to the nature of the optimization algorithm it is possible that a solution cannot be determined From previous testing it has been found that results can be obtained by changing the initial guesses to the solution algorithm consequently when GLHEPro cannot determine a solution the user will be prompted to change the initial guesses in the file HSizeInit dat located in the Lib subdirectory There are four values in this file the depth ratio between the HGSHP size and the base GSHP size the load ratio specifying the percentage of loads handled by the supplemental device and initial step sizes for these two values Typical initial guesses might range between 0 6 and 0 9 for the depth ratio
27. region or examining the data itself on the Peak Cooling Day worksheet shows that the 3 hour duration is closer to one Using the 3 hour duration in GLHEPro will slightly underpredict the peak temperatures using the 4 hour duration in GLHEPro will slightly overpredict the peak temperatures 90 Cooling Day Temperature Response 1 200 1 000 0 800 Hourly Response Duration 2 hr a 0 600 iid Duration 3 hr avg Duration 4 hr avg max Figure E0 10 Sample cooling response averaging method If the peak load calculation method is changed to maximum mode and the same durations are run the graph in Error Reference source not found results The 2 hour duration results in a normalized temperature response that peaks very close to one and would be an acceptable choice resulting in GLHEPro slightly overpredicting the peak temperature So in this case either peak load calculation method could be used the average over duration method with a 3 hour or 4 hour duration or the maximum method with a 2 hour duration The average over duration method with a 3 hour duration is the closest match 91 Cooling Day Temperature Response Hourly Response Duration 2 hr max Duration 3 hr max Duration 4 hr max Figure E0 11 Sample cooling response maximum method The procedure just described should be performed on both the heati
28. secondary inputs such as vapor pressures soil moisture and vegetation height are extremely difficult to compute or measure especially in more developed locales They also vary substantially with the seasons This method is mentioned here for the sake of completeness Results of this method seem to vary significantly with deviations on the order of 2 5 C 4 5 F from measured data The user is warned that either of the methods described above are very rough approximations We still recommend in situ testing to measure the actual ground temperature at your location 79 APPENDIX E PEAK LOAD DURATION TOOL 80 Peak Load Analysis Tool James R Cullin james cullin okstate edu Introduction As part of determining the temperature response of ground loop heat exchanger systems the short term response due to peak loads is an important factor Previously very little guidance has been available to users regarding peak loads The Peak Load Analysis Tool was designed as a way to provide users of GLHEPro a simple method for determining the value and duration for the monthly heat pump loads This tool consists of a VBA program fronted by a Microsoft Excel user interface which is designed to be as easy to operate as possible In order to use this tool users need sequence of hourly loads preferably 8760 a full year hourly values The program allows the user to compare simulations of the ground heat exchanger for both actual peak load day
29. the undisturbed ground temperature from the average yearly air temperature was introduced in Section 2 1 4 This approximation is based on work done by Signorelli and Kohl 2004 and expansion of those results to the continental United States Before attempting to use this method be warned that this approximation may not be good for your particular location especially if the climate at your location is extreme either frequently very warm or snowy for example The mapping approach undertaken by Signorelli and Kohl first fit both ground and air temperatures yearly averages as third degree polynomials against altitude The values for both temperatures were taken from meteorological stations around Switzerland Once the air temperature was modified to exclude subzero values as these were likely to be snowy intervals in which the snow would insulate the ground a nearly constant difference between air and ground temperature with respect to altitude above sea level was found the ground was on average 1 4 C 2 5 F warmer than the air This difference was applied to a previously generated map of the average annual air temperature in Switzerland and compared to existing ground temperature data from borehole systems scattered throughout the country A maximum deviation of 2 C was found during this verification By comparing available ground temperature references to available annual average temperatures for a variety of locations around the cont
30. 0 This line displays the brand manufacturer and the model of the heat pump The heat pump will be selected using The Total flow rate for entire system E or default 31 6401 seal This is the total min 10 dialog boxes that will define different brands and their models of the heat pumps For complete instructions see section 2 1 6 The Glhepro dialog box is also used to calculate the borehole thermal resistance and to select and or modify the borehole configuration soil type ground temperature circulating fluid and heat pump These six options are displayed as push buttons in the Glhepro Dialog Box The following six sections 2 1 1 to 2 1 6 describe the purpose of each option and how to use each one correctly and efficiently 2 1 1 Calculate Borehole Thermal Resistance In order to perform a simulation of the ground loop heat exchanger or to determine the required depth of the borehole s the g function and borehole thermal resistance of the ground loop heat exchanger system are needed Figure 2 4a shows the dialog box used to enter the necessary input data for single U tube configurations The g function will be dependent upon the geometry of the borehole The borehole thermal resistance is the resistance between the working fluid in the U tube and the borehole wall hereafter called the borehole resistance In GLHEPro the multipole method Claesson and Bennett 1987 Bennett et al 1987 is used to calculate the borehole therma
31. 1600 3332244 2091528 Heating Cooling 36 14008 50029 80928 F Average over duration 9 Average over duration 92 1412002 18 00 385283 2822857 Maximum during duration Maximum during duration 93 14020021900 0 0 94 420022000 0 0 Duration 1 Duration 4 35 1402002200 0 0 s 420022200 0 0 Note that itis not necessarily the case that the best method for 1020022200 0 0 heating and cooling average or maximum will be the same 98 542002 0 0 99 1612002000 0 0 100 1502002200 0 0 Get Summary Data 101 1612002300 0 102 1612002400 0 0 103 1512002500 0 0 104 1612002600 0 0 Total Loads 1000 Btu Peak Loads 1000 Btu h 105 1612002700 0 0 Heating Cooling _ Heating Cooling 106 1512002800 0 0 January 46446541 29032436 1881510 726 74463 Io import these loads into GLHEPRO 107 16120023800 0 0 February 22257706 58220154 1672428 1279 8753 8 15020021000 0 March 1018822 81828529 7786708 12214228 Select the range from 0 to 1101 inclusive 109 1512002100 0 0 April 284528049 16001 07 4292752 172423 5 Cops this to the clipboard CTRL C 10 15420021200 0 0 May 295894225 2045257 9224906 19503743 In GLHEPRO make sure that the units are English m 195120021500 0 0 June 0 3346 47 0 19662308 the menu bar select Loads gt Edit Heat Pump Loads n 154200214 00 0 0 July 0 42954156 0 2242597 Press first the Clear button then the Paste button 15200215000 0 August 0 3884102 0 2297 5 Manually enter the peak
32. 2 35000 119 40000 137 3910 3915 3920 3925 3930 3935 3940 Time Hours Figure 2 30 Cooling loads for a peak day Young 2004 40 2 2 43 Edit GLHE Monthly Loads This option is used to review or to manually enter the monthly total and peak loads direct on the ground loop heat exchanger GLHE To use this feature choose the Edit GLHE Loads option from the Loads menu This option brings up Edit GLHE Loads dialog box The Edit GLHE Loads dialog box is similar to the Edit Heat Pump Loads dialog box shown in Figure 2 28 The same features as in the Edit Heat Pump Loads dialog box are also provided in this dialog box and work in the same manner Why would someone wish to use direct GLHE loads For any application where either a heat pump is not used or where a heat pump is used only part of the year direct GLHE loads may be useful Some possible applications that could be modeled with the GLHE loads are e Fan coil units OR heated chilled beams Large buildings or campuses may use circulated chilled heated water to condition their buildings In this case any loads that are to be met by the heated chilled beams or fan coil units are placed on the GLHE If heat pumps are used instead of or in combination with fan coil units their loads must be placed in the Heat Pump Monthly Loads e cooling towers Cooling towers may be needed for systems that are cooling dominated and have negligible heating loads in order to prevent the GLHE f
33. 60 142 22 8 88 February 12790 51 374 93 0 02 0 00 March 1489 06 782 44 0 00 0 00 1 1771 07 1757 18 0 00 0 00 2 90 5432 43 0 02 0 00 June 8 88 9171 39 8 88 8 88 July 0 00 11711 49 0 00 72 92 August 0 00 11840 09 0 00 0 00 September 0 00 5749 83 8 88 8 88 October 100 79 4482 77 8 88 8 88 November 2176 89 794 35 0 00 0 00 0 02 0 00 December 16810 69 396 52 J Peak Heating Hours 3 Peak Cooling Hours 2 w tee Figure 2 38 Monthly Loads Section of GLHEPro Outputs The various simulation results are shown in the Results or Temperature Summary section of the output file and are essentially a copy of the useful data given in the Results pane when a simulation or sizing routine has been concluded The section title will indicate if the results are simulation sizing or hybrid sizing results If the results were generated by a sizing routine then the Borehole Information displayed indicates the borehole design required by the sizing criteria and used in the Monthly Temperature Summary The minimum and maximum Average Temperature shown in this section is not just the maximum and minimum of the average fluid 50 temperature Average temperature is used to mean the entering fluid temperature of the heat pump at the end of the month due to the average monthly loads applied on the system The minimum and maximum peak temperatures are found by adding the peak heating or cooling load in addition to the monthly average load and c
34. A small form is also present that serves the same purpose as the Input Form but allows the user to iterate more quickly once all parameters have been input Below this are two graphs that depict the heating and cooling load profile for the peak days On the second half of the interface see Figure E0 2 are graphs representing the normalized temperature response to the peak heating and cooling loads The response for the full set of hourly loads on the peak day is plotted along with the three selected approximations These will be explained in more detail later At the bottom of the interface portion of the worksheet there is a form that allows the user to determine the monthly peak heating and cooling loads from their best approximations This form outputs the loads in a format that is quickly transferable to the GLHEPro interface 81 ls e 2 gl al aloo l le lal A Date Time 1 2002 1 00 1002002 2 00 1002002 3 00 10102002 4 00 12002 5 00 11 2002 6 00 1 2002 7 00 1 2002 8 00 1002002 9 00 11 2002 10 00 1102002 1100 1 2002 12 00 4 2002 13 00 11 2002 14 00 1 2002 15 00 4 2002 16 00 472002 17 00 11 2002 18 00 11 2002 19 00 10 2002 20 00 1 2002 2100 1 2002 22 00 4012002 23 00 10212002 10212002 100 1242002 2 00 12 2002 3 00 2 2002 4 00 1212002 5 00 10212002 6 00 10202002 7 00 19212002 8 00 12 2002 9 00 10212002 10 00 10212002 100 10212002 12 00 10212002 13 00 10212002 14 00 10212002 15 00
35. GLHEPro 4 1 For Windows Users Guide Draft December 9 2014 School of Mechanical and Aerospace Engineering Oklahoma State University Distributed by the International Ground Source Heat Pump Association TABLE OF CONTENTS Po evitan e 1 PEEPLES COT m Sahiba tibia ah hae L 2 gt COV vc PRU MEN 2 2 Backrounds ona dpa eua care Lex C UE 4 1 3 tii t 4 4 TOC CUL cease a e 5 1 5 Program Technical Support iocis ce eO RP HI E cus 6 2 a Usine la a ise bi iae aes 7 AE DEO ALO DOX C nse Mace aes 7 2 1 1 Calculate Borehole Thermal eheu eo ran dero tiger tese 11 2 1 2 Select Borehole Configuration crest t tener teorie ente uaa 19 2 1 3 Select Ground Patameltets seco oues ies kx oon a e ac ed STRUD RS 21 2 1 4 Select Ground Temp rature esee in tuse e s 25 21 3 elect Fluid P lt oett aic cu 28 Z6 Select Heat ae et Met Eu 31 2 2 GLHEPro Main Menu and Toolbar Functions
36. The user should use GLHEPro for Windows to investigate the sensitivity of borehole length relative to the uncertainty in the ground thermal conductivity When in doubt entering a lower thermal conductivity will result in a more conservative longer borehole length thus longer pipe loop lengths Additional guidance may be found in the EPRI Soil and Rock Classification manual Bose 1989 Btu KJ Btu or ft F m K ft F The same references cited above can be used to evaluate the volumetric heat capacity GLHEPro for Windows contains data for a number of common soil types See section 2 1 3 The Undisturbed ground temperature C or F default 59 F In most locations the undisturbed ground temperature varies only a few degrees from the surface to the bottom of the borehole Because of this the undisturbed ground temperature can be estimated as the temperature at mid depth of borehole or D H 2 from the surface Experimentally it can be determined by circulating fluid through the boreholes and letting the fluid reach a steady state temperature See Gehlin and Nordell 2003 for more information on experimental determination This steady state temperature represents the undisturbed ground temperature for the borehole See Section 2 1 4 for more information including another method that may be useful for users outside the continental U S The Fluid type currently entered default Pure Water This line displays the fluid used for c
37. Where QC Cooling rate QH Heating rate EFT The temperature of the fluid entering the heat pump a b c d e f Constants determined by curve fit function of the program for the cooling mode Uu V W X y z Constants determined by curve fit function of the program for the heating mode If the user needs to model a heat pump not already in the library they may choose Add from the Maintenance section of the Select Heat Pump dialog box shown in Figure A 1 59 Select Heat Pump Currently Selected Pump is from Standard library Brand Name ClimateMaster Model Cooling Library Utility Heat of Rejection QC a b EFT c EFT 2 kBtu hr Power e EFT f EFT 2 kBtu hr 1 079521 d 0 023248 b 0 000621 e 0 000185 c 0 000016 f 0 000005 Heating Heat of Absorption QH u v EFT w EFT 2 kBtu hr Power QH x y EFT z EFT 2 kBtu hr 0644526 X 0 104982 V 0 003129 0 000949 Cooling Loads w 0 000016 z 0 000005 QC Cooling load kBtu hr kBtu hr QH Heating load kBtu hr kBtu hr EFT Fluid temperature entering the Heat pump F Export data to HVACSIM 565 parameter file Figure A 1 Select Heat pump dialog box To use this option the user will be required to enter heat pump performance data from the heat pump manufacturer s catalog We will be concerned with seven pieces of information from this catalog given over a range of con
38. Windows then returns to the Glhepro dialog box 2 2 1 3 Save As Default This option is used to save the present configuration of GLHEPro for Windows as the default When GLHEPro first starts each time it is run this default file will be read The default file name is default gli take care not to modify this file outside of GLHEPro as it may cause the program to load improperly or incompletely Note that the original default file is saved within the program installation directory and may require administrator access to manipulate outside of GLHEPro The modified default gli file may be saved to MyDocuments GLHEPRO Data in V4 1 5 or to C Users username AppData Local VirtualStore Program Files x86 GLHEPRO for previous versions 2 2 1 4 Page Setup This option is used to set the properties of the printer like printer name paper size paper source and the orientation of the paper These options will also be displayed when print is selected This item functions identically to other Windows programs 2 2 1 5 Exit This option is used to exit GLHEPro for Windows You may exit GLHEPro for Windows by either choosing Exit option from the File menu or by choosing Close option from the application s System menu box Before exiting GLHEPro for Windows will prompt you to save your input data see Figure 2 26 If you wish to save the system state click Yes and the Save As dialog box appears if there is no input data file ope
39. a F P and D P DeWitt 1990 Fundamentals of Heat and Mass Transfer 3 Edition New York Wiley Mills A F 1992 Heat Transfer Homewood Irwin Mitchell J K and T C Kao 1978 Measurement of Soil Thermal Resistivity Journal of the Geotechnical Engineering Division Proceedings of the ASCE Vol 104 No GT7 pp 1307 1320 Paul N D 1996 The Effect of Grout Thermal Conductivity on Vertical Geothermal Heat Exchanger Design and Performance Master of Science Thesis South Dakota State University Pikul Jr J L 1991 Estimating soil surface temperature from meteorological data Soil Science Vol 151 No 3 pp 187 195 56 Rees S J 2000 An Introduction to the Finite Volume Method Tutorial series Oklahoma State University Stillwater OK Safanda J D Rajver A Correia and P D de ek 2006 Monitoring of the Air Ground Temperature Coupling in Three European Climatic Provinces Geophysical Research Abstracts Vol 8 07663 Sanner B G Hellstr m J Spitler and S Gehlin 2005 Thermal Response Test Current Status and World Wide Application Proceedings World Geothermal Congress 2005 Antalya Turkey April 24 29 Signorelli S and T Kohl 2004 Regional ground surface temperature mapping from meteorological data Global and Planetary Change 40 267 284 Stolpe J 1970 Soil Thermal Resistivity Measured Simply and Accurately IEEE Transactions on Power Apparatus and Systems Vol PAS 89 No 2
40. alculating the resulting end of month temperature Simulation Results Borehole Information Each Borehole Design Depth ft 150 00 Total Borehole Depth ft 450 00 Distance between borehole centers ft 15 00 Average Temperature the End of Month Temperature due to Average Monthly Loads Maximum Average Temperature F Minimum Average Temperature F 108 03 at month 8 18 56 at month 1 Peak temperature 205 24 at month 7 33 94 at month 1 Maximum Peak Temperature F Minimum Peak Temperature F Figure 2 39 Results Section of GLHEPro Outputs for a Simulation Finally the Monthly Temperature Summary contains a month by month account of the behavior of the GLHE system as described by the following quantities heat extraction rate per unit borehole length heat pump power consumption fluid temperature and the average temperatures entering and exiting the heat pump as well as the peak values of the heat pump entering temperature The heat pump power consumption or HP Energy is an approximation of the energy consumed by the heat pump if it were to run at the Average or month end temperature This monthly summary is the same data that is written to the CSV file as mentioned below if that option is selected 51 Monthly Temperature Summary Note EWT Entering water temperature to heat
41. already attempted to register once Please keep a copy of your Registration e mail for future reference Once you ve obtained a registration number from us you enter it by selecting Register from the Registration menu After entering the registration code you will have to exit and restart GLHEPro before all of the features are available Your License number should now be displayed under the help option About GLHEPro for your future reference on GLHEPro V4 1 4 and later 1 5 Program Technical Support Technical support for GLHEPro is provided by the Building and Environmental Thermal Systems Research Group at Oklahoma State University Any questions or problems you have concerning GLHEPro can be sent to glhepro okstate edu We will attempt to respond within one working day Information about some of our more frequently asked questions is available on our website at https hvac okstate edu glhepro faq 2 USING GLHEPRO FOR WINDOWS GLHEPro for Windows is a user friendly software package The dialog boxes that you will encounter are straightforward and provide you with an easy method of entering your design data The dialog boxes consist of edit controls list boxes combo boxes push buttons check buttons and radio buttons in which data can be entered or selected GLHEPro for Windows starts with the Glhepro Dialog Box 21 Glhepro dialog box The first dialog box that the user encounters is the Glhepro Dialog Box This dialog box is
42. anger loop Figure 2 3 is a top view of an example borehole radius that does not use a casing ee ee Edge of drilled borehole 74 Heat Exchanger Pipe Figure 2 3 The borehole radius for a single U tube borehole that does not use a casing A top view of the borehole r is estimated as the radius of the drilled hole e The Borehole thermal resistance default 2 0 3607 x or The Vm borehole thermal resistance is the resistance between the heat carrier fluid and the borehole wall This total resistance depends on the thermal conductivity of the ground the borehole radius the thermal conductivity of the medium inside the borehole but outside of the heat exchanger pipes and the number of pipes and their position in the borehole The borehole thermal resistance also depends on the thermal resistance of the borehole wall and between the bulk fluid in the pipes and the inner pipe wall This value is computed automatically by GLHEPro when the g function is created For complete instructions see section 2 1 1 e The Borehole Spacing in or m default 15 ft This is the center to center spacing between the boreholes The ratio between the borehole spacing and the depth per borehole is an important factor in computing the long time step g function It is possible for this ratio to fall outside the boundaries of the data used to compute the g function While unlikely to happen for any typical borehole co
43. ar Fit Quadratic Fit Performance Data I S o E 5 2 5 o Temperature F Figure A 11 A comparison of the linear and quadratic curve fits for the Heat of Absorption vs Total Heating equation Linear Fit Quadratic Fit Performance Data Power Total Heating Temperature F Figure A 12 A comparison of the linear and quadratic curve fits for Heating Power vs Total Heating equation 70 From the above plots we can see that the best curve fits are the quadratic curve fits It might be helpful for the designer to take the time to plot the results of their curve fits to determine which best predicts the performance of their heat pump Now that you have the heat pump curve fit coefficients you are ready to continue using GLHEPro for Windows 71 APPENDIX B INTERFACING GLHEPRO FOR WINDOWS 72 This appendix briefly describes the use of two building energy analysis load calculation programs to generate monthly loads and peak loads for use with GLHEPro for Windows These programs are e Trane System Analyzer e HVAC Load Calculation for Windows Trane System Analyzer The use of Trane System Analyzer to generate monthly and peak loads for use with GLHEPro is very straightforward After describing the building and system and running the system analysis the user should choose Export Geothermal Output from the File menu The program will the
44. arameters button will call the secondary input form shown in Figure E5 on which the specific numeric values of certain system parameters may be input Most users should never need this option the secondary parameters have a small effect 84 on the peak temperature response A sensitivity analysis showed that changing any single parameter resulted in a difference in the normalized temperature response on the order of 2 3 Changing multiple parameters simultaneously yielded little additional difference On the other hand changing the fluid factor results in a difference on the order of 5 10 in the temperature response depending on the difference between the two values compared For that reason the fluid factor is included as a primary input while the other less important to this analysis not to the system parameters are listed in the secondary form Finally there are two options for calculating the peak load as opposed to the duration though the duration is affected by the method for calculating the peak load e Selecting Maximum over duration will simply cause the program to look for the absolute maximum load during the design day and apply it continuously for each hour of the peak duration e Selecting Average over duration will cause the program to determine the highest cumulative load over the day for the duration specified and average this sum for the number of hours in the duration to determine the value of the pea
45. ased on empirical equation fits If the user enters a configuration larger than 20 by 20 boreholes a warning will be issued Since the empirical equation fits were based only on data for borehole fields smaller than 20 by 20 selecting a field larger than this is basically an extrapolation of an approximation While doing this has been shown to produce reasonable results it has not been possible to check these values against experimental or detailed simulation results 2 1 3 Select Ground Parameters GLHEPro offers an automated method of entering the necessary ground properties namely the thermal conductivity and the volumetric heat capacity These properties can be entered directly into Glhepro Dialog Box if they are known Alternatively a dialog box can be used to select ground properties from a library To use this feature click the Select Ground Parameters button Figure 2 11 shows the Soil Properties dialog box that will appear This dialog box contains a table of various soil types The table displays data from two sources GLHEPro comes along with two libraries the standard library and the user library Data from the standard library is displayed in black and data from the user library are displayed in blue The standard library contains data from sources such as ASHRAE while the user library contains custom soil types stored by the user 21 0 51745 14 0 50012 0 19901 Black Cotton Soil 0 63421 Red Soil 0 5778 Sand Gypsu
46. ating Mode EWT F GPM Ent Air Total Watts Heat Rej Ent Air Heating Heat of Abs Watts W B F Btuh Input Btuh D B F Btuh Btuh Input 10 0 63 79000 5300 97000 60 65000 46000 5500 45 0 67 84000 5340 102000 70 63000 44000 5800 13 0 63 83000 5100 100000 60 68000 49000 5500 67 88000 5110 105000 70 67000 46000 5800 10 0 63 77000 5500 96000 60 70000 51000 5700 50 0 67 82000 5600 101000 70 68000 48000 5900 13 0 63 81000 5400 99000 60 73000 53000 5700 67 86000 5450 104000 70 71000 50000 6000 10 0 63 75000 6200 54000 60 89000 58000 6100 60 0 67 79000 6220 45000 70 77000 55000 6400 13 0 63 78000 5900 98000 60 82000 61000 6100 67 83000 6000 103000 70 80000 58000 6500 10 0 63 72000 6800 95000 60 88000 65000 6500 70 0 67 76000 6850 99000 70 85000 62000 6900 13 0 63 75000 6500 97000 60 91000 69000 6600 67 80000 6600 102000 70 88000 65000 6900 10 0 63 60000 7200 84000 85 0 67 63000 7300 88000 13 0 63 63000 7000 86000 67 66000 7020 90000 10 0 63 53000 8000 80000 100 0 67 56000 8100 83000 13 0 63 55000 7800 82000 67 58000 7830 85000 Figure A 2 The manufacturer s performance data for 6 ton heat pump 62 Add Heat Pump Brand Name Model Curve Fit _ Enter Cooling Loads Linear Fit Quadratic Enter Heating Loads Type of Curve Figure A 3 Add Heat Pump dialog box Once these parameters a
47. d borehole length to meet the user specified minimum and maximum temperatures entering the heat pump The desired maximum and minimum temperatures the first and last months and the output data file can be edited by clicking the mouse in those boxes and typing in the new values The same convention holds for the month numbers and output file location as described earlier You may run GLHESize for as many months as you choose but 10 or 20 years will probably be an appropriate simulation length for almost any application In most cases after 20 years there is little change in the steady periodic temperature profile Once GLHEPro for Windows has determined the required Active Borehole Depth to meet the required fluid temperature entering the heat pump a simulation is run for the range of months that you have entered While running this simulation a data file is created which is identical in format to that which is created when GLHESim is run When GLHESize has completed its calculations the Glhepro Results dialog box Figure 2 34 appears with all of the data as described in Section 2 2 6 1 45 2 2 6 3 Perform Hybrid GSHP Sizing The ability to size a hybrid ground source heat pump HGSHP system was added to GLHEPro version 4 0 HGSHP systems consist of a ground loop heat exchanger just like a normal GSHP system plus an added heat source solar collector boiler etc or heat sink cooling tower fluid cooler etc device The added heat rejection
48. d in black and the data from the user library will be displayed in blue The standard library contains data for a few less commonly used antifreeze mixtures 28 Fluid Properties Fluid Type selected GS4 Water X Freezing Point Weight Mean Temp F rH Thermal Conductivity Btu hr ft F Volumetric Heat Viscosity Density lb ft Btu CF ft Ibm ft h 6 77348 _ 1778039 Current Fluid is from the GLHEPro Standard Library Maintenance Library Utility Figure 2 18 The Fluid Properties dialog box used to select a mixture type for the circulating fluid After selecting the row that corresponds to the fluid that is to be used click the Select button or double click on that row to confirm your selection Click Cancel to exit without selecting a circulating fluid from the library If a fluid was selected from the library GLHEPro for Windows then returns to the main window and updates the appropriate lines If a matching fluid type is not found the user can store a custom fluid type in the user library by clicking the Add button on the Fluid Properties dialog box Figure 2 19 shows the Add Fluid Properties dialog box that will appear The user can enter a new fluid type or select one of the fluid types from the user library by clicking the arrow present at the right side of the Fluid Type box and then making a selection out of the scrolling list that will appear
49. data correctly entered your screen should be identical to that in Figure A 4 Once all data has been entered correctly press OK to return to the Add Heat Pump dialog box Now if you wish to view the curves click the type of curve at present you have two options Heat of Rejection QC vs Temp and Power QC vs Temp that you wish to see and click View Curve to view that curve Figure A 7 Click CLOSE to return back to Add Heat Pump dialog box Cooling Mode Performance Data Total Cooling Heat of Rejection Power Input kBtu hr kBtu hr KW 83 100 5 1 81 99 54 78 98 5 9 75 65 63 7 0 55 7 8 Figure A 4 Cooling mode performance data dialog box Enter Heating Loads This option is used to enter the heating mode performance data of the heat pump s to be modeled To enter heating data click the Enter Heating loads on the Add Heat Pump dialog box and Heating Mode Performance Data dialog box appears From the performance data sheet for this heat pump Figure A 2 enter the Entering Water Temperature degree F the Total Heating kBtu Hour the Heat of Absorption kBtu Hour and the Power input kW Assume that we are operating at 13 GPM with an Entering Air D B of 70 F Again be careful to use the correct units and to enter the data accurately To make it easier to input data into the form you can use the Paste and Clear buttons Format the data for input in a table and copy it to the clipboard
50. desired This is purely a text editor there are no formatting options available in this notepad These notes are preserved along with all of the variables when a file is saved and may also be printed to a file after running a simulation sizing procedure 47 Project Notes Figure 2 37 Adding notes to the project 2 5 GLHEPro Outputs GLHEPro has several output options that can be selected by the user in the Output File Preferences box Figure 2 33 The selected outputs are generated each time it completes a simulation or sizing routine The name of the default output file is glhewin glo If the name or location of the output file is not changed by the user between simulations the original output file will be overwritten with the new simulation results There are a total three different output files and six different items that are reported in the main output file for a simulation or sizing run Some of the contents of the output files that require more explanation are detailed below The first information included in the main GLO output file which is not listed on the Output File Preferences box Figure 2 33 is the same Notes as described in section 2 2 8 This will always be the beginning of the file along with the name of the input file model and the time the simulation occurred 48 Project Name Default Notes Default file File Model Name Simulated On 10 6 2014 1 20 41 PM Simulated By Rachel Grundma
51. ditions The entering water temperature The heat rejection rate The total sensible latent cooling rate or cooling capacity The power input in the cooling mode The heat extraction rate The total heating rate or heating capacity The power input in the heating mode 60 Example To demonstrate the use of this option of adding heat pumps we will determine the curve fits and hence the twelve heat pump coefficients for a 6 Ton heat pump The performance data for this heat pump is given in Figure A 2 The first dialog box that appears when Add Heat Pump is activated is shown in Figure A 3 On this dialog box you will need to select whether you prefer a linear or quadratic curve fit although it can be changed depending on the results A brand name and model name should be entered to describe the heat pump For this tutorial we will determine both a linear and a quadratic curve fit for six cooling mode points and four heating mode points The number of points for each mode is not necessarily equal Let us begin by determining a quadratic curve fit for our heat pump data To select a Quadratic curve fit click Quadratic Fit from the Add Heat Pump dialog box shown in Figure A 3 Note that in the cooling mode the sheet contains data for six different entering water temperatures and in the heating mode there are data listed for four different entering water temperatures 61 Cooling Mode He
52. durations the proper bozes n 19512002 16 00 0 September 853542204 30503403 32040681 946682 Continue using GLHEPRO as normal 15 10512002 17 00 0 0 October 21640655 206267 96 4085493 1902 9585 e wsi20020800 0 0 November 170295283 69757706 1190 574 1185 9783 17 15420021900 0 0 December 429575961 28320368 2069456 60394075 Te 1520022000 0 0 n 1512002200 0 0 120 1520022200 0 0 Ya 1520022300 0 0 122 1612002 0 0 123 1620021000 0 124 i Wo Control Sheet Heating Peak Cooling Day Cooling Response _ Monthly Loads 141 olf y AutoShapes w og L A Iv oC 2 Read NUM Figure E0 2 Peak Load Analysis Tool interface bottom half 1 Load Entry The first step in the analysis of peak loads using the Peak Load Analysis Tool is the entry of the hourly heating and cooling loads for the year This is done simply by copying the loads from an external source into columns A through C on the main sheet The sign convention expected by the program is that heating loads are positive while cooling loads are negative Referring to Figure E0 3 note that the tool expects the first load 1 January 12 00am to occur in row 3 It may be necessary to add or remove header lines from the load source file to accommodate this In addition cells B2 and C2 are intended to be the units for the heating and cooling loads respectively any text placed in these cells will be o
53. e After the fluid has been selected and the concentration and mean temperature specified click the Calculate Properties button to update the property table Closing this dialog box will return the user to the main GLHEPro window and the changes to the fluid properties will be reflected in the fluid property table on the window Select Antifreeze Mixture Select Fluid Characteristics Concentration Wt96 0 Fluid Type Pure Water cited Mean Temperature 68 po Average Temperature 68 F Library Fluid Vat nM Fluid Concentration 0 Freezing Point Density Volumetric Heat Capacity Conductivity Viscosity d Ib ft Btu F ft Btu hr ft F Ibm ft h 32 62 31 6223 0 343 2 42333 Close Figure 2 17 Using the Select Antifreeze Mixture dialog box to select a mixture type and concentration for the circulating fluid Although GLHEPro contains data for all of the commonly used antifreeze mixtures the user may still desire to utilize a different fluid type For this purpose the fluid library exists To access the library click the Library button The Fluid Properties window shown in Figure 2 18 will appear This dialog box contains a table of properties for different concentrations of various fluid types This table displays data from two sources the standard library and the user library As was also the case for soils data from standard library will be displaye
54. e Diameter D2 in Volumetric Flow Rate borehole gal min Fluid Factor Unitless multiply fluid in the system by this amount Volumetric Heat Capacities Thermal Conductivities Soil 32 21 j Btu F ft Soit 1 Btu hr ft F Grout 58 166 Btu CF ft Grout 0 4298 Btu hr ft F Pipe 22 992 Btu F ft Pipe 0 2247 Btu hr ft F Options for specifying the fluid convection coefficient C Entered Value Convection Coefficient 1269 109 Btu hr ft F Reynolds Number NA m Calculated Value Fluid Type Pure Water Fluid Concentration 0 Average Temperature 68 F Volumetric Heat Capacity Btul F fe Conductivity Btul hr f F 0 343 G Function Calculations Calculate Borehole Resistance Export G Function to File Borehole Resistance Viscosity ibit 2 42333 Figure 2 4a Borehole resistance calculator main form Options for specifying the fluid convection coefficient Entered Value Convection Coefficient 1269 109 Btu hr ft F Reynolds Number N A Calculated Value Fluid Type Pure Water Fluid Concentration 0 Average Temperature 68 F Select Fluid Freezing Point Density Capacity Volumetric Heat Conductivity Viscosity 1 Btul F f Btu hr ft F Ibm ft h 6231 6223 G Function Calculations Calculate Borehole Resistance Export G Function to File Borehole Resistance 0 343 2 42333 0 3609 F Btu hr ft Figure 2 4b Bor
55. e of the Brand combo box and select the desired brand by clicking it Similarly a model can be selected GLHEPro for Windows will automatically update the coefficients If GLHEPro for Windows does not include the manufacturer or the particular model of heat pump that you will be using in your design then you may elect to calculate the heat pump coefficients by clicking Add Heat Pump from the Select Heat Pump dialog box GLHEPro for Windows uses the performance data published by the manufacturer and calculates either linear or quadratic curve fits Usually a quadratic curve fit will more closely match the manufacturer s data This computed data could be stored in the user library for later use The heat pump data stored in the user library can later be modified or deleted The user will be permitted to modify or delete only the heat pump data stored in the user library For complete instructions on how to use the Add Heat Pump option please refer to Appendix A of this manual Users can import and export user heat pump data by making use of the import and export features incorporated in the Select Heat Pump dialog box To use the export feature click the Export button on the Select Heat Pump dialog box Figure 2 24 shows the dialog box that will appear Select the desired option and click A Save As dialog box similar to the one shown in Figure 2 14 will appear Enter the name of the file where the heat pump data is to be sa
56. e step g function are extrapolated if the ratio between borehole spacing and borehole depth lies outside the range of available data Results may or may not be correct but the user is so warned Minor functionality improvements Flow rate inputs in SI units are now in liters per second and several length inputs in SI units are now in millimeters GLHEPro for Windows now recognizes Trane System Analyzer heat pump load files with the extensions GTH GT1 GT2 GT3 and GT4 The serial number can now be copied directly to the clipboard Library changes 459 new heat pump models have been implemented bringing the current total to 843 See Appendix C for details as well as for information on the naming convention 55 REFERENCES Most OSU theses and papers co authored by Dr Spitler are available at the Building and Environmental Thermal Systems Research Group website www hvac okstate edu Austin W A 1998 Development of an In Situ System for Measuring Ground Thermal Properties Master s thesis Oklahoma State University Stillwater Oklahoma Also available at http www hvac okstate edu pdfs Austin_thesis pdf Austin W C Yavuzturk and J D Spitler 2000 Development Of An In Situ System For Measuring Ground Thermal Properties ASHRAE Transactions 106 1 365 379 Bennet J J Claesson and G Hellstr m 1987 Multipole Method to Compute the Conductive Heat Flows to and Between Pipes in a Composite Cylinder Note
57. eat 0 01 10 0 04187 41 87 Ns m Volumetric Heat 1 100 67 07 6707 ve S Each soil type is uniquely identified by its description so no soil types can have the same description The user will not be permitted to enter a soil type with the same description as any of the soil types from the standard library If the user enters a soil type with the same description as any one of the soil types from the user library he will be asked to confirm overwriting the existing one The user can also modify the soil types that exist in the user library To use this feature select the row containing the soil that is to be modified and then click the Modify button A dialog box which is exactly the same as the Add Soil Properties box will appear with the various text boxes already containing the properties of the soil being modified The validation rules which apply to adding a soil type are the same as those for modifying a soil type The user may also modify the description of the soil type but cannot change the description to one already possessed by a different soil type in the user library The user can also delete any of the soil types from the user library To use this feature select the row containing the soil that is to be deleted then click the Delete button The user will be asked for confirmation before deletion The user cannot modify or delete any of the soil types from the standard library The Modify
58. ee Appendix C for details as well as for information on the naming conventions e All databases have been internalized 32 Additions to Version 4 0 Significant program changes e The program is capable of modeling large rectangular borefields up to 900 boreholes GLHEPro can be purchased in three different versions e GLHEPro 4 0 120 Contains 307 different borehole configurations between 1 and 120 boreholes Configurations include lines L shaped fields U shaped fields open rectangular fields and rectangular fields e GLHEPro 4 0 LRO Contains only large rectangular borefields 100 boreholes and larger The algorithms used to create the g functions were based on configurations of up to 400 boreholes in size Beyond 400 boreholes the program is extrapolating the results e GLHEPro 4 0 400 Contains all configurations in GLHEPro 4 0 120 and GLHEPro 4 0 LRO 54 Contains a feature for sizing ground loop heat exchangers and supplemental heat sinks or sources used as part of a hybrid ground source heat pump system The thermal mass of the fluid within the borehole is included in the short term response The thermal mass of the fluid outside the borehole can now be included by specifying a Fluid Factor gt 1 This can have a moderate effect on GLHE size for systems that are dominated by peak loads The calculation of borehole thermal resistance has been improved by utilizing the multipole method Bennett et al 1987 Convective re
59. ehole resistance calculator 12 U Tube Double U Tube Concentric U Tube Borehole Specification Borehole Diameter d 4 33 in Shank Spacing s 0 7441 in _set_ o U Tube Inside Diameter D1 0 8583 in d Ons U Tube Outside Diameter D2 1 0512 in Volumetric Flow Rate borehole 10 5468 gal min Fluid Factor 1 Unitless multiply fluid in the system by this amount Volumetric Heat Capacities Thermal Conductivities 32 21 Btu F ft 3 Soil 1 Btu hr ft F Grout 58 1664 Btu CF ft 3 Grout 0 43 Btu hr ft F Pipe 22 9922 Btu F ft 3 Pipe 0 225 Btu hr ft F Figure 2 4c Borehole resistance calculator single U tube Shank Spacing 1 9213 in _set_ Q U Tube Inside Diameter 01 0 8583 in U Tube Outside Diameter 02 1 0512 B Volumetric Flow Rate borehole 10 5468 gal min Fluid Factor 4 Unitless multiply fluid in the system by this amount Sot 3224 Btu F f 3 Sok 4 22 Btu hr ft F Grout 581664 Btu CF ft 3 Grout 043 Btu hr ft F Pipe 230071 Btu F ft 3 Pipe 0225 Btu hr ft F Figure 2 4d Borehole resistance calculator double U tube 13 U Tube Double U Tube Concentric U Tube Borehole Specification Borehole Diameter d 4 33 in D2 InnerTube Inside Diameter D4 0 9843 in InnerTube Outside Diameter D3 1 2992 in OuterTube Inside Diameter D2 3 4252 se d 63 OuterTube Outside Diameter D1
60. ell as the final design conditions including borehole loop temperatures heat extraction rate per unit length of borehole and power consumption by the heat pump 1 2 Background The best methods currently available for design of vertical borehole systems are those based on Eskilson Eskilson 1987 as have been implemented in the GLHEPro for Windows computer software Eskilson s method depends on the use of g functions which represent the temperature response of a given borehole configuration to a step change in heat extraction or rejection rate The g functions are computed using a finite difference model which is not part of the design software developed by Eskilson nor is it included with the GLHEPro for Windows package This limits the user to borehole configurations that have been pre computed Currently there are 307 pre computed borehole configurations included in the GLHEPro for Windows package Additionally equation fits have been developed that approximate to a reasonable degree of accuracy larger rectangular borehole fields 13 Installation GLHEPro for Windows can be installed onto your hard drive while running Microsoft Windows 7 or earlier versions XP 95 98 NT 2000 It is available via electronic download or with a physical CD ROM If you requested an electronic download follow the link provided to you in an e mail and save the file to your drive Extract the contents of the zip drive and double click on the setu
61. en empirically found that this is indeed the case for most of the cases examined The program then copies the loads for these days onto the Peak Heating Day and Peak Cooling Day worksheets along with the numerical day of the year provided for reference 3 Parameter Input To change the program control parameters click the Launch Input Form button located at the top center of the main sheet The primary input form shown in Figure E0 4 will appear On this form the user should enter three different integer values one each into each of the heating and cooling peak duration text boxes Entering values less than one or greater than 24 will generate an error message as will entering non numeric values entering a non integer numeric value will not produce an error but the fractional portion of the entry will be truncated not rounded The three values initially chosen by the user are really three guesses as to the peak load duration They can then be adjusted in a trial and error fashion Several other items are also located on this control sheet The fluid factor is a multiplier that gives the amount of fluid in the system relative to the amount of fluid in the U tube A fluid factor of two for example would indicate that the total fluid in the system including the U tube is twice what is in the U tube As the amount of fluid in the system increases the peak temperature response decreases In addition clicking the Edit Secondary P
62. eoStar Aston Series Roth RXT Enertech XT Addison DWY HWY PWY VY Series McQuay Console 60 Hz RWD RWH Horizontal Unit Vertical Unit Series Waterfurnace E Series Premier Versatec Horizontal Vertical VLC Series 5 Series NS ND Legend LS ClimateMaster CCE GCH GCV GCH V GLH GLV GSH V RE TS VHS Series TY TS TC TR TCH V TZ Trane XR Series TIGC XL Series T2GE Econar QxxKWxT GV GH GC GV GH 520 590 670 GH Series Econar GV GH 380 480 580 Series 80 F DB 67 F WB Cooling 70 F DB Heating 68 F Heating Econar GW GW GV GH Series Bosch SM CE SV TW Could not be determined from manufacturer s specifications McQuay Console 50 Hz Series Trane XL Series TIGN T2GN T1GX T2GX 27 C DB 19 C WB Cooling 21 C DB Heating 20 C DB Heating Florida Heat Pump Aquarius AP Series Florida Heat Pump MC Series 70 F DB 61 WB Cooling 70 F DB Heating 70 F WB Cooling Note Source GPMs and load side CFM used to develop equation fits are included in the title of each unit Heat pump series added or expanded in version 4 1 Table C 1 Water Source Water to air Heat Pumps 75 Heat Pump Data Load Source Load GPM Load EXWT GPM Trane EXWA 240 53 6 55 55 Trane Axiom EXW 70 Trane WPWD Series 53 6 7 7 Trane XL Se
63. er specified minimum and maximum temperature entering the heat pump This can be done with or without a supplementary heating cooling unit Third GLHEPro can output parameter files for either the HVACSIM or EnergyPlus simulation programs These parameter files contain the inputs necessary for simulating a ground heat exchanger on an hourly or sub hourly time step GLHEPro for Windows operates with a Graphical User Interface GUI and dialog boxes that the user will find easy to understand and simple to use Each dialog box consists of information pertaining to one portion of the design process such as the borehole configuration ground properties heat pump used or the selection of circulating fluid properties 11 Overview Figure 1 1 is a flowchart which gives an overview of how GLHEPro for Windows operates what input parameters are required and what the final results are GLHEPro for Windows requires three basic sets of input data which will be explained in greater detail in Chapter 2 Monthly heating and cooling loads on the heat pump These are obtainable using a building thermal analysis program such as but not limited to HVAC Load Calculations for Windows Trane System Analyzer Trane Trace Carrier HAP DOE 2 or eQuest These monthly loads must then be entered into GLHEPro for Windows GLHEPro for Windows offers automated methods for transferring the monthly loads if they were determined using either of the Trane programs In addi
64. exchanger pipe spacing and ground as well as grout thermal properties are also required User description of the heat pump GLHEPro for Windows uses four curve fit equations to describe the performance of the heat pump GLHEPro for Windows supplies the user with default curve fits and some standard curve fits provided by different manufacturers of heat pumps but if the user so desires he she may describe the performance of a specific heat pump and compute the coefficients to match that specific heat pump User Description of Building User Description of Bulding Loads D 4 Ground Loop Heat 7777 Analysis Sotware __ User Description Exchanger Heat Pump GLHEPRO User Interface GLHESIM GLHESIZE Data File Which Data File Which Contains Contains User Input Data User Input Data Monthly Loop Borehole Depth Temperatures Monthly Loop Power Consumption Temperatures Power Consumption Figure 1 1 Flow Chart of the operation of GLHEPro for Windows GLHEPro for Windows will either run a simulation up to a maximum of 1200 months using the GLHESIM algorithm or it will size the depth of the borehole s using the GLHESIZE algorithm to meet a specified maximum and minimum temperature entering the heat pump for a given borehole configuration When either of these options are run GLHEPro for Windows creates a data file that contains the user input parameters as w
65. exchanger In this case the user should choose a typical heat pump that represents the average heat pump 32 To view the four curve fits described above click View Curve push button of Select Heat Pump dialog box using the mouse Figure 2 22 is the dialog box in which the user may specify which particular heat pump to view Type of Curve Heat of Rejection QC vs Temperature Power QC vs Temperature Heat of Absorption QH vs Temperature Power QH vs Temperature Figure 2 22 Dialog box for selection of heat pump curve to view From this dialog box select a type of curve and click Plot button to view the pop chart of the curve fit A sample pop chart of the curve fit for the heat of rejection vs the total cooling capacity is shown in Figure 2 23 If you move the mouse over the chart it will show you the coordinates for the current location on the chart Heat of Rejection QC vs Temperature 60 80 Temperature F Figure 2 23 Sample heat pump curve pop chart Click Close to close the Pop Chart dialog box and come back to Select Type of Curve dialog box Click Close again to return to Select Heat Pump dialog box You may also select a heat pump brand and model from a list of heat pump brands manufacturers and models included with GLHEPro for Windows from the Select Heat 33 Pump dialog box To select a brand manufacturer click the arrow mark present at the right extrem
66. exit without editing the loads 5 If you are the developer of another building energy analysis program that can generate monthly and peak loads on the heat pumps and would like information on interfacing to GLHEPRO please contact Dr Spitler 37 Date modified No items match your search 22280 8989 434 6043 12790 5092 374 9259 1489 0579 782 4378 1771 0713 1757 1839 2 9003 5432 434 0 9171 3887 0 11711 4881 0 11840 0917 0 5749 8312 100 7946 4482 7672 2176 0923 794 3462 16810 6925 396 5248 o o o o o o o Duration of Peak Loads Number of Peak heating hours 3 Number of Peak Cooling hours 2 Figure 2 28 The Edit Loads dialog box 38 2 24 2 Edit Heat Pump Monthly Loads This option is used to review or to enter manually the monthly total and peak loads for the Heat pump To use this feature choose the Edit Heat Pump Loads option from the Loads menu This option brings up Edit Heat Pump Loads dialog box that looks exactly like the Read Loads dialog box Figure 2 28 shows the Edit Loads dialog box with edited loads The monthly total loads must be entered in 1000 BTU or in KW hr and the monthly peak loads in 1000 BTU hr or in kW depending on the unit system that the user has chosen for the input and output data see Section 2 2 5 To enter a heating or cooling load use the
67. g box Set U Tube Spacing Single U Tube Spacing 7 59 6 2 ao as B Figure 2 5 Spacing options for a single U tube system Set U Tube Spacing Double U Tube B O 69 A0 O as e B Oc Caution These spacing configurations are NOT the same as for a single U Tube Figure 2 5b Spacing options for a double U tube system 15 The U tube Inside and Outside Diameter in or mm default 0 8583 in 1 0512 in The defaults are the inside and outside diameter respectively of an SDR 11 pipe of nominal pipe size 4 in GLHEPro for Windows contains data for a number of common pipe types and nominal pipe sizes from which the user may select shown for IP units as Figure 2 6 The dialog box for Figure 2 6 is shown when the user presses the Set button next to the Inside Diameter text box In SI units DN pipe sizes are shown Regardless of the units the user may enter actual pipe inner and outer diameters for any pipe Set U Tube Diameters Pipe Type Nominal Pipe Size SDR 1 114 Schedule 40 1 9 11 2 Figure 2 6a Set U tube Diameters dialog box IP Set U Tube Diameters Nominal Pipe Size 7 DN25 DN40 gt DN32 DNSO Figure 2 6b Set U tube Diameters dialog box 81 The Volumetric Flow Rate borehole or default 10 5468 eal This is the min 5 min flow rate through each individual borehole It is the total volumetric flow rate g
68. ght 96 as any one of the records from the user library the user will be asked for confirmation before overwriting the existing record 2 1 6 Select Heat Pump This option is used to select and or to add the coefficients used for the heat pump curve fits To use this feature click the Select Heat pump push button using the mouse Four curve fits are used in GLHEPro for Windows two for the cooling mode and two for the heating mode The four equations describe 1 the heat of rejection vs the total cooling capacity 2 the power required by the heat pump vs the total cooling capacity 3 the heat of absorption vs the total heating capacity and 4 the power required by the heat pump vs the total heating capacity Each of the four equations is a function of the fluid temperature entering the heat pump The default for each is a quadratic curve fit for a series of currently available heat pumps GLHEPro for Windows is also able to handle linear heat pump curve fits Figure 2 21 is the Select Heat Pump dialog box with the brand manufacturer name and model name The heat pump data displayed in this dialog box might either be from the standard library or from the user library The standard library contains heat pump data of seven different major 3 term capacity is used here to mean the actual total sensible latent heat transfer to or from the inside coil under a given operating condition 3l manufacturers with over 1000 hea
69. h regular snow cover A description of the theory behind this approximation as well as another method that could be used to estimate ground temperature may be found in Appendix D GLHEPro offers a simple implementation of the above method To begin click the International Locations button located on the Select Ground Temperature sheet The non U S temperature selection form will appear as shown in Figure 2 16b If your location is one of those listed simply select it and press the Select button If not data may be added by clicking the respective button In the form that appears enter the city country and average annual air temperature and click Save Note that this is air temperature you are entering here and not ground temperature if you know the undisturbed ground temperature already simply enter that value in the main window Upon returning to the international temperature selection form select your new entry entries are automatically sorted alphabetically by country then city and press Select You may also modify the temperature of any record or delete a record entirely with confirmation of course by pressing the corresponding button An in situ test Austin 1998 Austin et al 2000 Witte et al 2002 Sanner et al 2005 is recommended to determine ground temperature and other thermal properties instead of trusting tabulated data or approximations although these can still be useful for preliminary estimates
70. he name of the file where the soil data is to be saved into the proper box The export feature creates a text file with extension lib or csv which contains the information about the various user defined soil types in a specific format When the Ground Properties dialog box displays search results the Export button will be enabled only if the search result contains at least one soil type from the user library Using the export feature when search results are displayed will result in exporting only those soil types from the user library that match the specified search criteria export Soil Properties QO GLHEPRO lib s Search 1 p Organize v New folder Hz v e gt BE Desktop Name Date modified Type B Downloads Si Recent Places No items match your search i3 Libraries Documents 4 Music 7 i Pictures amp j Subversion Videos Computer amp Local Disk C Sg rgrundm stwfi _ lt File Excel Comma Seperated Values Library File Hide Folders Figure 2 14 Export Soil Types dialog box 24 To use the import feature click on the Import button on the Ground Properties dialog box Figure 2 15 shows the Open dialog box that will appear Select the file that contains the desired soil information and click Open This will read the lib or csv file created by exporting and store the information about the various soil
71. his feature select the appropriate fluid type from the drop down list box Select the row containing the record that has to be modified and click the Modify button A dialog box which is exactly the same as the Add Fluid Properties box will appear with the various text boxes containing the properties of the fluid record being modified The validation rules that apply to adding a fluid type also hold for modifying one as well As with soil entry the user cannot change the description and weight percent to that of a fluid record that already exists in the user library The user can also delete any of the fluid records from the user library To use this feature ensure that the correct fluid type is selected in the box that displays the fluid type description Select the row containing the record that is to be deleted then click the Delete button The user will be prompted for confirmation before deletion The user cannot modify or delete any of the fluid records from the standard library The Modify and Delete push buttons will be disabled when the fluid selected is from the standard library Users can export data from or import data into the user library by making use of the import and export features incorporated in the Fluid Properties dialog box To use the Export feature click on the Export button on the Fluid Properties dialog box Figure 2 20 shows the Select Fluid Type dialog box that will appear Select a
72. ience the ground temperature may be input in either unit system After inputting the desired temperature in one box clicking outside that box will automatically update the temperature in the other unit system In most locations the undisturbed ground temperature varies only a few degrees from the surface to the bottom of the borehole Because of this the undisturbed ground temperature can be estimated as the temperature at mid depth of borehole or D H 2 from the surface Experimentally it can be 25 determined by circulating fluid through the boreholes and letting the fluid reach a steady state temperature This steady state temperature represents the undisturbed ground temperature for the borehole For a more thorough discussion of this topic consult the paper by Gehlin and Hellstr m 2004 For international users another option is available It is possible to use the average annual air temperature for your particular location as a preliminary estimate of the undisturbed ground temperature Through some semi empirical observations it has been noted that the undisturbed ground temperature is typically about 2 5 F 1 4 C warmer than the annual average air temperature However we warn the user that this is only an approximation This has been checked for several U S locations and results seem to agree with the international data that has been found to date however this is probably not very accurate in more extreme climates i e wit
73. inental United States it would seem that the air temperature might be a reasonable approximation for the undisturbed ground temperature As shown below the difference between the two varies a bit more substantially than Signorelli and Kohl found for Switzerland however For the following cities annual average air temperatures were taken from the web and ground temperatures were estimated from Figure 2 15a Annual Avg Air Ground City Temp F Temp F Difference F Atlanta GA 61 3 64 227 Chicago IL 49 0 51 2 0 Denver CO 50 3 52 1 7 Detroit MI 48 6 51 2 4 Fargo ND 41 0 47 6 0 Houston TX 67 9 74 6 1 Kansas City MO 53 6 55 1 4 Los Angeles CA 63 0 64 1 0 New York NY 54 7 56 1 3 Oklahoma City OK 60 0 62 2 0 Phoenix AZ 72 6 68 4 6 San Francisco CA 57 1 59 1 9 Seattle WA 52 8 53 0 2 AVERAGE 1 85 Further research would be needed to establish good explanations for the range of differences seen here Presumably such factors as vegetation humidity radiation to the sky solar radiation 78 incident on the ground snow cover etc all have an effect Results taken from measurements in the Czech Republic and Portugal seem to be in line with the 2 5 F empirical estimation Safanda et al 2006 for normal grass vegetation There is also an energy balance method developed by Pikul 1991 based on thermal resistances to compute the ground temperature using the air temperature as one of the inputs However many of the
74. ing Loads Edit Heat Pump Loads from the menu bar The load editor shown in Figure will appear To transfer the loads from the clipboard into GLHEPro first click the Clear Loads button and then click the Paste button The values will then appear in the load editor Next manually enter the peak heating and cooling load durations as found by using the Peak Load Analysis Tool into their respective text boxes Click OK to save these loads and return to the main window of GLHEPro If for some reason the loads fail to copy properly clear them and try again The pasting must be done via the Paste button within GLHEProO however and not by pressing CTRL V or using any other clipboard management technique 93 Edit Loads on Heat Pump Load on Heat pump NE Total Heating Total Cooling Peak Heating Peak Cooling EU 1000 Btu 1000 Btu 1000 Btu hr 1000 Btu hr rims 147064243 Febuary 1330586305 5582 Mach pusossos 53056 Api 55085 7060587737 463063056 Mey 8794090 3744737 m sensn feer Augus 0177848872 356599 2965 0 053282957 2170 417474 September 286 3084521 248757 352 56 74214547 1904 923178 October 7027 44561 151813 8233 435 8366284 1502 533934 November 20523 74363 46016 62418 757 4656246 1053 464055 December 69558 58389 7213 620121 1515 238967 159 0570042 Duration
75. irculating through the boreholes The circulating fluid will be selected using dialog boxes that will define different fluids and their properties For complete instructions see section 2 1 5 The Volumetric heat capacity of the ground default 32 21 Btu KJ acr ca tF mK Btu F default is correct for pure water as the circulating fluid If another mixture will be used as the circulating fluid then this parameter will most likely need to be changed GLHEPro for Windows contains data for a number of common heat exchanger fluids See section 2 1 5 The The Volumetric heat capacity of the fluid default 62 2275 The Density of the fluid amp default 2 62 3112 Again the default is correct t m for pure water The density of other circulating fluids can be determined using tabulated values Bose 1988 GLHEPro for Windows offers an automated method of entering the fluid properties including the density and the volumetric heat capacity see Section 2 1 5 min S combined rate of flow through all the boreholes If you are using English units the flow rate must be entered in gallons per minute A common rule of thumb is to use greater than 2 5 gallons per minute per ton 12 000 Btu hour of the maximum load on the heat pump GLHEPro for Windows will issue a warning if the flow rate is lower than 2 5 gallons per minute per ton The Heat Pump default 2 ClimateMaster Classic Model 03
76. ity of the soil Btu or KJ default 32 21 Bu ft F m K 6 F This value comes directly from the main glhepro dialog box For more details see Section 2 1 3 The Volumetric heat capacity of the grout Btu or KJ default 58 166 Btu ft F f F The Volumetric heat capacity of the pipe ae or default 22 992 Btu ft F m K f E Btu W Btu Conductivity Of soil __ The Conductivity of soil m oF or m default 1 or fF This value also comes directly from the main Glhepro dialog box For more details see Section 2 1 3 The Conductivity of grout or sw default 20 430 a values of grout thermal conductivity are about 0 38 Btu hr ft F for standard Bentonite grout and about 0 85 Btu hr ft F for thermally enhanced grout Btu 2 W hr ft F Typical Btu fault 20 225 default 0 225 hr SF which is typical The Conductivity of pipe for HDPE pipe The Fluid Convection Coefficient Big AN 5 J defaut 1269 108 hr ft F m K Btu hr ft F rate and default fluid factor with pure water at 68 F as working fluid There are two options to get the convection coefficient between the working fluid and the tube wall The convection coefficient may either be specified directly by the user or it may be computed by the program itself Before using this option make sure that the value is correct
77. iven in the main window divided by the number of boreholes in the system It is automatically obtained from the main form As with borehole diameter changing this value will also change the value on the main form The Fluid Factor default 1 The fluid factor is defined as the ratio of the total fluid in the system to the fluid in the borehole U tube s In a ground loop heat exchanger system fluid in the U tube helps to damp the response to peak loads Furthermore fluid 16 outside the U tube but circulating through the system has the same effect it damps the response to peak loads In some systems the peak response can be critical in determining the required size of the ground loop heat exchanger Therefore it was desired to offer the capability of accounting for the thermal mass of the fluid both inside the U tube and in the rest of the system GLHEPro the fluid factor is used to estimate the effect of fluid inside and outside the U tube A system that had a negligible amount of fluid outside the boreholes would have a fluid factor of one A typical value of the fluid factor for an actual system including fluid in the borehole manifold piping and the distribution piping inside the building is two The fluid factor is particularly important in situations when the peak load duration is short and the magnitude of the peak loads are high For other cases the effect of the fluid factor is relatively small The Volumetric heat capac
78. k load The load will be applied starting at the beginning of the averaging interval if the averaging method is used or the location of the absolute maximum if the maximum method is used As an example assume that the peak heating day consists of a four hour set of heating loads with values of 150 800 650 and 500 kW Selecting the averaging method with a four hour duration will result in a peak approximation of 525 kW starting concurrently with the original 150 kW load Selecting the maximum method regardless of duration will result in a peak approximation of 800 kW with the load first applied at the same hour as the original 800 kW load If this is confusing run the same durations in both modes and notice the differences in the responses After selecting all of the primary parameters to exit the form and determine the response for the conditions entered To expedite this process during iteration a similar form is located on the body of the main worksheet so that peak durations and the peak load method may be easily altered without the unnecessary return to the input form Cancelling this form will return the user to the main sheet without changing any of the parameters or computing the temperature response 85 n Control Sheet Primary Parameters Input the primary system parameters on this sheet To enter hourly loads Cancel this form and paste loads into column B of the Main Sheet Heating Peak Durations
79. l resistance The dynamic short term response of the borehole to changes in the heat input is calculated at the same time The multipole method is a highly accurate analytical method and has compared very well to a two dimensional boundary fitted coordinate finite volume numerical model Rees 2000 The borehole resistance has three components the convective resistance between the working fluid and the tube wall the conductive resistance caused by the U tube and the resistance caused by the grouting material The convective resistance depends upon the convection coefficient between the working fluid and the tube wall The convection coefficient can be specified by the user or can be computed internally by GLHEPro More in depth discussion follows The pipe resistance is based on the standard expression for resistance of a hollow cylinder Incropera and DeWitt 1990 and is determined from the pipe thermal conductivity The default pipe has a conductivity of 0 225 Btu h ft F 0 39 W mK The user may change this value if a different pipe type is needed The grout resistance is the thermal resistance of the grouting material This is dependent upon the thermal conductivity of the grout and the pipe geometry A typical value of grout thermal conductivity is 0 38 Btu h ft F 0 66 W mK for standard Bentonite grout Thermally enhanced grouts can have a range of conductivities which should be available from the manufacturer One of the first thermal
80. ly enhanced grouts had a conductivity of 0 85 Btu h ft F 1 5 W mK and grouts with conductivity in excess of 1 2 Btu h ft F 2 1 W mK are on the market Other parameters to be entered along with their respective default values into the G function and Borehole Resistance Calculator form are listed below Users can select a double U tube or concentric tube configuration in addition to the single U tube configuration The double U tube configuration is composed of a pair of U tubes oriented 11 perpendicularly to one another The inputs for this configuration borehole diameter d shank spacing s and inner and outer pipe diameters D7 and D2 are identical to those for a single U tube configuration The concentric tube configuration consists of both an inner and an outer pipe dimensions and thermal properties for these two pipes may be specified independently from one another Diagrams of these configurations can be seen in the G Function and Borehole Resistance Calculator dialog boxes for the respective configurations Figures 2 4a c show in IP units the G function and Borehole Resistance Calculator dialog boxes for each of three borehole configurations single U tube double U tube and concentric tube G Function and Borehole Resistance Calculator U Tube Double U Tube Concentric Borehole Specification Borehole Diameter d 4 Shank Spacing s 0 in U Tube Inside Diameter 01 0 in U Tube Outsid
81. m 0 60083 Selected Data is from the GLHEPro Standard library Cae Figure 2 11 The ground properties dialog box To select the thermal and physical properties for the ground simply double click the row containing the corresponding soil type GLHEPro for Windows then returns to the Glhepro Dialog Box and updates the appropriate lines Click Select or double click the row containing the corresponding soil type to confirm your selection Click Cancel to exit without selecting a soil type The user may also store custom soil types in the user library by clicking the Add button on the Soil Properties dialog box Figure 2 12 shows the dialog box that will appear After entering the data for the user soil type press to continue and save the soil type to the user library Select the units of the data to be added or modified Limits on user imputs are specified in the GLHEPro Manual Table 2 1 7 Metric kJ m K V English Btu ft Example Limestone solid 1 32294 163 00421 0 21687 Figure 2 12 Add Soil Properties Dialog box 22 The property values are checked for egregious errors Permissible values of various properties are as follows Table 2 1 Range of permissible values for various properties of User s Soil Conductivity QI ED ae 01731 1731 W Ib kg Density 10 10 000 1 160 18 1 6 5 of Specific H
82. maximum Cooling Peak Duration 2 3 load during the peak das and uses this value Cooling Peak Duration 3 4 throughout the peak duration Review and revise secondary input parameters as desired This is not Peak Determination Mode Average entirely necessary as these parameters do not have a large 3 act on the response calculation Amigo omi Gaalon Press OK on the input form or the button to the right to generate response graphs Maximum during duration for both the peak day and the three peak Visually decide which approzimation is nearest the true response profile This may require several runs of the program with different 1 durations andfor peak methods Calculate Pesk Responses the Monthly Loads form area below enter the heating and cooling peak methods and durations and click the button This will generate both total and peak loads for each month for use in GLHEPRO See instructions nest to the Monthly Loads form to use these loads in GLHEPRO Heating Load Profile Cooling Load Profile 700 300 200 600 700 _ 500 p 500 1 400 500 3 3 P300 poo H Bav 200 200 100 m 04 4 8 12 16 20 24 4 12 16 20 24 Hour Hour Figure E0 1 Peak Load Analysis Tool interface top half 82 Microsoft Excel Peak Load Analysis Tool
83. ms of the loads over each month To agree with the sign convention anticipated by GLHEPro cooling loads are at this point negated so as to result in a positive value 92 Monthly Loads Heating Cooling Average over duration Average over duration Maximum during duration Maximum during duration Duration 3 Duration 9 Note that it is not necessarily the case that the best method for heating and cooling average or maximum will be the same Get Summary Data Total Loads 1000 Btu Peak Loads 1000 Btu h Heatin Coolin Heatin Coolin January 111463 847 6239 6933 1861 4988 147 064249 February 60730 9344 10076 631 1330 58631 164 585318 March 19146 1278 31450 556 529 542288 584 534267 April 7385 66198 70605 877 469 063226 1258 87553 May 930 954085 219706 89 73 7494182 137447432 June 1 18618085 293216 79 0 39539362 2089 57852 July 0 391541 59 0 1858 30907 August 0 17784887 3565993 0 05928296 2170 41747 September 286 308452 248757 35 56 7421455 1904 92318 October 7027 44561 151813 82 435 836628 1502 53934 November 20523 7436 46016 624 757 465625 1053 46405 December 69558 5839 7213 6201 1515 23897 159 057004 Figure E0 12 Monthly load form and output Now that the loads are known they can be exported into GLHEPro To do this highlight the range of cells containing the loads not including row or column headers and copy this data to the clipboard In GLHEPro bring up the heat pump load editor by select
84. n option and then click the Ok button A Save As dialog box the same as that shown in Figure 2 14 except with only the lib file extension option will appear Enter the name of the file that is to contain the fluid properties data Exporting a fluid type creates a text file with extension lib which contains the information about the fluid types from the user library in a 30 specific format The user can use the export feature only when the currently displayed fluid type is from the user library the Export button will be disabled when the currently displayed fluid type is from the standard library Select Fluids for Export Export the current Fluid only Export all the fluids from the User library 9 Figure 2 20 Select Fluid Type dialog box To use the import feature click on the Import push button on the Fluid Properties dialog box An Open dialog box similar to the one shown in Figure 2 15 will appear Select the file that contains the information about the various fluid types Importing reads the library file created by exporting and stores the information about the fluid types in the user library If the library file being imported contains a record with the same fluid type description as any one of the records from the standard library the record will not be added to the user library However if the library file contains a record which has the same fluid type Description and Wei
85. n query the user to specify which alternative to use for the geothermal data Selecting the ground source option the program will then report to the user that the geothermal output file has been successfully created This file will have the same name as the System Analyzer data file with the extension gth instead of azr From GLHEPro for Windows use the Read Loads option from Loads menu For file type choose the Sys Analyzer GTH File name extensions of GT1 GT2 GT3 and GT4 are also supported HVAC Load Calculations for Windows HVAC Load Calculations for Windows is specifically aimed at generating design peak loads and monthly loads for GLHEPro for Windows In order to create a loads input file for GLHEPro for Windows all the user needs to do is to check the Create gll file box on the Annual Simulation Setup dialog box The Annual Simulation Setup dialog box is brought up by choosing Annual Energy Analysis under the calculate menu The program will create a gll file with the same name as the building file e g demo gll created when the file demo blg is being used 73 APPENDIX C INFORMATION ON NEW HEAT PUMPS 74 Heat Pump Series Entering Air Trane GECA GEH GERA GET GEV GEH V WPHF WPV J Series Axiom Florida Heat Pump LV 80 6 F DB 67 or 66 2 F WB Cooling 68 F DB Heating Florida Heat Pump CA CS EC EM ES EV GS GT MB Series G
86. ned the same way as the Save option handles You may also exit GLHEPro for Windows without saving your data by clicking No If you change your mind click Cancel and GLHEPro for Windows will return to the Glhepro dialog box Note that if you do not save your data the data cannot be recovered and will be lost permanently Create New File o untitled is not saved Save now xe Figure 2 26 Exiting GLHEPro for Windows 36 2 2 2 View Output File This option is used to preview the output file produced before printing It gives a view of how the file would look if opened in a text editor Also as the output file is created only after running SIM or SIZE this option is disabled before running SIM or SIZE for a given input file The units displayed in the output file match the units of the most recent simulation 2 2 3 Print This option is used to print the output file As the output file is created only after running SIM or SIZE this option is disabled before running SIM or SIZE See section 2 3 for information on the contents of the output file 2 2 4 Loads The following functions allow users to define and edit the monthly loads on the heat pump and ground loop heat exchanger system 2 2 41 Read Heat Pump Loads From a File This item is found in the Loads menu and is used to read the monthly total and peak heating and cooling loads on the heat pumps from an output file that was created by a b
87. nfiguration used with a ground source heat pump system it is possible and in this case the user would receive a warning message when attempting to simulate or size the GLHE See Section 2 2 6 1 The Borehole Geometry default Line Configuration 3 1 X 3 line This line displays the borehole configuration that will be used for the design process The borehole configuration will be selected using dialog boxes that will define the pattern of the boreholes and the spacing between the borehole centers For complete instructions see section 2 1 2 e The Thermal conductivity of the ground or bal default 1 There hr ft F m K are four methods currently available for evaluation of soil thermal properties laboratory analysis Stolpe 1970 Mitchell and Kao 1978 use of a thermal probe Mitchell and Kao 1978 Hooper and Chang 1953 Falvey 1968 classification by soil type Bose 1989 Bose 1988 and in situ tests Austin 1998 Austin et al 2000 Witte et al 2002 Sanner et al 2005 GLHEPro for Windows contains data for a number of common soil types from which 2 See Eskilson 1987 page 20 of Conductive Heat Extraction By A Deep Borehole Thermal Analysis and Dimensioning Rules 9 the user may select the ground properties best representing their local conditions See Section 2 1 3 for further details We caution the user that the final design is very sensitive to the actual ground thermal properties
88. ng and the cooling load profiles A good method to use is to start with durations of 1 2 and 3 hours and proceed upward from there until either the best fit for the method is found or it becomes apparent that that particular method will be insufficient to produce a desirable response to the peak loading when for example the peak response either always exceeds or never really approaches a value of one At that point switch to the other method and repeat the above steps Comparison of the best fit from each mode will produce the desired peak load duration and method It is quite likely that the peak durations will be different for heating and cooling and it may also be true that the best method for heating is not the same as that for cooling 5 Getting Monthly Peak Loads Once the best choices for heating and cooling peak duration and peak load method have been determined the peak loads for each individual month may be computed using the duration and method information At the bottom of the main worksheet s interface fill in the proper values of the heating and cooling peak duration into the form which is shown in Figure E0 12 In addition check the appropriate boxes for the peak load method for both heating and cooling Click the Get Summary Data button to compute the peak as well as total loads for each month of the year The peak loads are determined using the approximation entered into the form while the total loads are simply the su
89. ng data make certain that the units system you choose for your input data does indeed match the data that you have already entered or plan to enter Also even though it appears obvious be sure to use consistent units throughout your input data Inconsistent units will certainly result in erroneous designs FER GLHEPro untitled File Loads Units Action Help Register Da d vec puse 7 Borehole Pz English Active Borehole Depth Borehole Diameter 109 982 mm Borehole Thermal Resistance 0 2084 K WIm Calculate Borehole Borehole Spacing 4572 m Thermal Resistance Borehole Geometry LINE CONFIGURATION 3 1 x 3 line Ground Parameters Soil type currently entered Thermal Conductivity ofthe ground 1 731 WIK Select Ground Parameters Volumetric heat capacity ofthe ground 2160 2015 kJ K m 3 Select Ground Temperature Undisturbed ground temperature 15 bs Fluid Parameters Total flow rate for entire system 1 9962 Select Fluid Fluid Type Pure Water Fluid Concentration 0 Average Temperature 20 C Volumetric Heat a Capacity Conductivity Viscosity kGime3 kJ m 3 K Wi m K Pas 0 998 1007 4173 3625 0 5929 0 001 Freezing Point Density Heat Pump Heat Pump Selected ClimateMaster Classic Model 030 Select Heat Pump Figure 2 31 The Glhepro Dialog Box with data in metric units 2 2 6 Action The options available on the Action dr
90. nn Figure 2 38 Notes Section of GLHEPro Outputs Next are the System Parameters These include the system dimensions as well as properties of the soil and working fluid Note that the units of the outputs match the unit system used during the simulation The heading for this section will vary depending on whether a regular or hybrid simulation was performed If a sizing or hybrid sizing routine is used the Active borehole length is used as the initial guess length for the optimization program the actual design length is shown in the Results section of the output file System Parameters Active borehole length ft Borehole Radius in Borehole spacing ft Borehole Geometry Soil Type currently used 150 000 2 165 15 LINE CONFIGURATION gt 3B 1x 3 line Thermal conductivity of the ground Btu hr t F 1 Volumetric heat capacity of Ground Btu F t Volumetric heat capacity of fluid Btu F t Undisturbed ground temperature F Borehole thermal resistance F Btu hr t Fluid type currently entered Mass flow rate of the fluid gal min Density of the fluid 1b t Heat Pump Selected Figure 2 39 System Parameters Section of GLHEPro Outputs 32 21 62 2275 60 6 0 3609 Pure Water 31 641 62 3112 ClimateMaster Classic Model 030 The GLHE and Heat Pump Monthly Loads which are each optional outputs are displayed next This is simply a copy of the monthly loads as they appea
91. of Peak Loads Number of Peak heating hours 3 Number of Peak Cooling hours 9 Clear Loads Cancel Figure E13 GLHEPro heat pump load editor 6 Other Useful Things The Peak Load Analysis Tool supports both Metric 51 and English IP unit systems To change unit systems click the appropriate radio button located at the top right of the main sheet The conversion may take a few seconds depending on the speed of the computer being used as all 8760 hourly heating and cooling loads will be converted as well as several other items on the secondary worksheets Note that after changing units any specific daily load data entered on the Peak Heating Day or Peak Cooling Day worksheets column B will be overwritten so it is best to change the unit system before starting any work Basic instructions and reminders are located throughout the various worksheets The Heating Response and Cooling Response sheets contain full sized versions of the normalized temperature response plots which may be useful when determining the best duration and method Enjoy 94
92. op down menu are G Function Creator Perform Sim Perform Size and Hybrid GSHP Sizing The G Function Creator option opens the Borehole Thermal Resistance Calculator that is covered in detail in section 2 1 1 The other functions are explained in detail below 2 2 6 1 Run GLHESim This option is used to run a simulation of the performance of the ground loop heat exchanger that was defined in sections 2 1 and 2 2 4 To do this choose the Perform Simulation option from the Action menu This option brings up GLHESim Control Sheet dialog box as shown in Figure 2 32 42 You may run a simulation for as many months as you would like up to a maximum of 1200 months 100 years GLHEPro for Windows requires that you enter the number of the first month and the number of the last month of the time period that you wish to simulate The convention for the month numbers is that month 1 is January month 2 is February month 13 is January of the following year and so forth To run a simulation for say 10 years enter 1 for the first month and 120 10 years x 12 months per year for the last month This is done by clicking the mouse in those boxes and entering the desired values This dialog box also gets the name of the output file where the output data can be written GLHESim Control Sheet Duration of Sizing First month of simulation 1 Last month of simulation 100 Send output data to file glhewin glo File Preferences
93. ovide output of the g function of the borehole system for two other energy simulation programs HVACSIM and EnergyPlus To select the g function output single click the Select G function Print Format button Then check the box corresponding to the desired output format s and press Ok The HVACSIM parameter files there is one for Type 620 Type 621 and Type 628 can be read from the graphical HVACSIM interface The EnergyPlus parameter file contains a piece of the IDF file In both cases these files enable hourly or shorter time step simulation of the ground loop heat exchanger Output to Parameter Files Current depth 150 ft 7 Print HVACSIM Parameter File Print EnergyPlus IDF File Ok ls Figure 2 7 Select G function Print Version dialog box To change any of values single click the corresponding input box and type in the new value pay attention to the units Once you have set up the dialog box with the desired input data and geometry selections for the system single click the Calculate Thermal Resistance box to calculate the average borehole resistance The value of the borehole resistance will automatically print in the dialog box If you choose the second option to calculate the convection coefficient the value will also automatically print in the corresponding box Then choose OK to transfer the information back to the main Glhepro dialog box Pressing
94. p exe file If you requested a hard copy then insert the CD ROM into your CD drive Use Windows Explorer to examine the CD s directory and then double click on the setup icon or setup exe The installation program will then ask you to provide an installation path GLHEPro for Windows will be installed onto your hard drive in the specified installation path with a sub directory named Data which contains a default gli and a gfunc directory having GEqnFits txt gfunc txt and gfunc2 txt The main folder will also include DFORRTD DLL msvcrtd dll MULTIPOLE dll NPlot dll PG SerialKeyMaker API dll GFunc eed and an icon file These files are all necessary for the proper operation of the program and should not be modified The Peak Load Analysis Tool will also be included in the main file more information on this spreadsheet can be found in Appendix E A folder will also be created in your My Documents directory as a default location to save input and output files This directory is created to avoid the issues that occur when the main application installation and directory is saved in a protected location such as Program Files 1 4 Registration GLHEPro is copy protected When the program is initially installed certain important features e g selection of most borehole configurations and saving of files are restricted There are three license options for GLHEPro Demo 120 LRO and 400 Each option enables a certain number of borehole
95. pump s ExWT Exiting water temperature from heat pump s Average End of Month temperature due to Average Monthly Loads HP Energy Electrical Energy requirements of Heat Pump s Eck ke ce ce e ce ce ce ce EEE ce E EEE EEE EEE EEE EEE EEE EEE EEE EEE EEE EEE EEE EEE EEE EEE E E E EEE SEE EEE EEE ESSE EEE SESE ESTES TTT HP Average Average Minimum Maximum Time Q Energy Tf ExWT EWT EWT EWT months Btu hr ft kW hr F F F F F SEEKS ce ce ce E E ce ce E ce ce ce ce E S SSH GE ESSE ce cE c E E ce E E E E E E DIE DIE GE GE GE cE GE SESE c E E E E E 224422424222244424444224242222222422444424244 1 44 97 1996 39 17 92 17 28 18 56 33 94 18 56 2 29 32 1041 37 30 30 29 89 30 72 30 72 30 72 3 71 137 54 56 15 56 14 56 16 56 16 56 16 4 2 12 205 28 59 55 59 58 59 52 59 52 59 52 5 19 79 350 24 77 03 77 31 76 75 76 75 76 75 6 36 09 738 79 93 96 94 47 93 44 93 44 93 44 7 46 10 1090 23 105 56 106 22 104 91 104 91 205 24 8 47 04 1145 17 108 70 109 37 108 03 108 03 108 03 9 22 21 423 98 87 02 87 33 86 70 86 70 86 70 10 16 28 313 63 81 57 81 80 81 33 81 33 81 33 11 2 34 182 65 63 69 63 66 63 73 63 73 63 73 12 35 25 1352 56 31 42 30 92 31 92 31 92 31 92 Figure 2 40 Monthly Temperature Summary Section of GLHEPro Outputs In addition to the typical GLO output file two other output files may also be generated depending on whether either of the first two boxes in the Output File Preferences dialog box Figure 2 33 has been checked Checking the
96. r copy make sure you provide all the necessary information to the online registration form and include a comment on why you require a new registration code 52 Registration Error 2 The registration code was copied incorrectly or is of the wrong format In the case of the latter contact glhepro okstate edu with your problem Extreme Temperature in GLHESIM indicates that the fluid temperature simulated was outside the reasonable range for the given month If this message occurs during a simulation it is followed by the message Please makes sure you have entered correct values and try again and the simulation results are discarded If it occurs during a sizing routine it indicates that an iteration found results outside the acceptable range This does not mean that the final results are incorrect Sizing Failed Sizing Iterations failed to converge within 100 iterations The sizing routine attempts to find a borehole depth that allows the system to reach both the minimum and maximum temperature specified in the given simulation duration If it cannot meet either of these constraints it usually signifies that you should reconsider your constraints on temperature and simulation duration loads or borehole configuration Fatal error encountered inputs were provided in the wrong form and could not be converted to usable data numeric or Boolean Make sure to use the proper form of inputs Other characters that sometimes cause is
97. r in the Edit GLHE or Heat Pump Monthly Loads menu option The peak load durations are displayed beneath each table of loads 49 GLHE Monthly Loads e e e e e EE EE c ce ce c c ce E E E DE DE DIE DIE DIE DE GE EE E E E E E E E E E DIE DIE GE DIE DE DE E E E E E E E E E E DIE DIE DIE DIE DIE IE IE OE E E E OE 0E 0E 0E IE E E E E AEG Month Total Heating Total Cooling Peak Heating Peak Cooling 1000 Btu 1000 Btu 1000 Btu Hr 1000 Btu Hr Gk ke ce ce ce ce ce e cce GE c E c 2E DE cC E GE E E c E GE 3E E GE E GE GE E GE cC DE cE E DE 2E E GE cC GE GE E GE GE E GE E GE 3E E GE 2E GE c IE IE E IE GE IE IE E IE GE GE IE GE E e 0E IG X January 8 88 0 00 0 00 0 00 February 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 1 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 June 0 00 0 00 0 00 0 00 July 0 00 0 00 0 00 0 00 August 8 88 8 88 8 88 8 88 September 8 88 8 88 8 808 8 88 October 0 02 0 02 0 00 0 00 November 0 00 0 00 0 00 0 00 December 0 00 0 00 0 00 0 00 2 2 Peak Heating Hours 3 Peak Cooling Hours 2 w we Heat Pump Monthly Loads Month Total Heating Total Cooling Peak Heating Peak Cooling 1000 Btu 1000 Btu 1000 Btu Hr 1000 Btu Hr Eck ke ce ce ce ce ce ce ce ce ce ce e ce SEES ESSE SESE ce DE ce E DE SESE SEES ESS ESSE SESS E E DIE 3E IE GE E GE GE IE GE cE IE GE IE DIE E IE E E E E E A E GG January 22280 90 434
98. re entered correctly the Add Heat Pump dialog box has three options to choose from Enter Cooling Loads which is used to enter the performance data of the heat pump in the cooling mode Enter Heating Loads which is used to enter the performance data of the heat pump in the heating mode Cancel which is used to exit Add Heat Pump and return to the Glhewin dialog box Enter Cooling Loads This option is used to enter the cooling mode performance data of the heat pump s to be modeled To enter cooling data click the Enter Cooling Loads on the Add Heat Pump dialog box and Cooling Mode Performance Data dialog box appears From the performance data sheet for this heat pump Figure A 2 enter the Entering Water Temperature degrees F the Total Cooling kBtu Hour the Heat of Rejection kBtu Hour and the Power input KW For this tutorial we will assume a flow rate of 13 GPM with an Entering Air W B of 63 F Itis extremely important that the performance data is entered correctly Incorrectly input performance data will result in erroneous curve fits and the design of the heat exchanger will be adversely affected make it easier to input data into the form you can use the Paste and Clear 63 buttons Format the data for input in a table and copy it to the clipboard then press the Paste button to load the data into the form The data must be a table of 4 columns and may have up to 10 rows When you have the
99. ries TIGW 70 Cooling 5 5 62 Cooling 80 Heating Enertech WT Series 45 F Cooling 95 F Heating Roth RWT 80 F Cooling 110 F Heating Addison WWR Series 55 Cooling 100 Heating McQuay GRW Series ClimateMaster GSW 60 Cooling Series 100 Heating Florida Heat Pump WP 45 F Cooling WW Series 110 F Heating Note Source GPMs used to develop equation fits are included in the title of each unit Heat pump series added or expanded in version 4 1 Table C 2 Water to Water Heat Pumps Nomenclature The title of each unit or heat pump typically consists of the manufacturer s name designations for the heat pump or heat pump series Additional specifications are listed below for cases when multiple data sets are available for a specific heat pump model i e for variable speed fans blowers or compressors Note that this data is only specified if it is needed to find the specific record in the manufacturer s data High Speed Low Speed may be referred to in full or as HS LS or High Low Part Load Full Load may be referred to as pl fl or Part Full Entering Load Temperature may be referred to as ELS or LS in F unless otherwise specified H C specified heating cooling values ECM PSC motor specification Dual or DC dual capacity motor specification 55 55 Single Speed 5 Speed motor specification 76 APPENDIX D MORE ON UNDISTURBED GROUND TEMPERATURE 77 A method for estimating
100. rom locally increasing the ground temperature and reducing system efficiency The cooling tower loads would be placed directly on the GLHE as a heating load because heat is extracted from the ground and rejected to the air e heated bridge decks A ground source heat pump can be used to heat a bridge deck In the summer energy is stored in the ground by circulating fluid directly from the bridge deck to the GLHE In this case the winter heating loads required to de ice the deck are entered as heat pump loads The summer recharging energy is entered as a cooling load direct on the GLHE A common misuse of the GLHE loads option is to place duplicate loads on both the heat pump and the ground loop While this situation may occur it does so rarely and this more often causes the GLHE to be oversized by a factor of two by mistake 2 2 5 Units This option is used to change the units of the input and the output data The default for both input and output data is the English units system To change units to metric choose the Metric option from the Units menu On changing units from English to metric GLHEPro for Windows automatically converts all the data to metric units Figure 2 31 shows the default Glhepro dialog box in Metric units Similarly you can also change the units from metric to English by choosing English from the Units menu GLHEPro then automatically converts all the data to English IP units 41 If you are enteri
101. s and peak loads applied for various durations By adjusting the duration of the peak load the user can choose the best representation of the hourly loads To determine the values different for each month of the year and durations constant for the year of the peak heating and cooling loads with the peak load analysis tool a multi step process is used 1 Entry of hourly heating and cooling loads for the year 8760 loads in total 2 Determination of the peak heating and cooling days for the year 3 Input of system characteristics if desired 4 Iterative determination of best heating and cooling peak load durations 5 Retrieval of peak heating and cooling loads for each month Each of the above items will be discussed in more detail First however the main interface will be discussed Upon loading the Peak Load Analysis Tool will show the main sheet on which the entire analysis process may be done if desired The other worksheets show either the same data in a different scale or show additional data such as the numeric values plotted on the graphs that can also be utilized On the main sheet see Figure 0 1 the three leftmost columns contain the 8760 hourly heating and cooling loads for the entire year By convention heating loads are positive and cooling loads are negative At the top of the worksheet are buttons which serve three of the five items enumerated above as well as radio buttons to select the unit system
102. s on Heat Transfer 3 1987 Department of Building Technology and Mathematical Physics University of Lund Sweden Bose J E 1988 Closed Loop Ground Source Heat Pump Systems Installation Guide National Rural Electric Cooperative Association NRECA Research Project 86 1 Bose J E Editor 1989 Soil and Rock Classification for the Design of Ground Coupled Heat Pump Systems Field Manual Electric Power Research Institute Special Report EPRI CU 6600 Claesson J and Hellstr m 1987 Thermal Resistances to and Between Pipes in a Composite Cylinder Department of Mathematical Physics and Building Technology University of Lund Sweden Eskilson P 1987 Thermal Analysis of Heat Extraction Boreholes Ph D Dissertation University of Lund Sweden Department of Mathematical Physics Falvey D M 1968 Increase Accuracy of Soil Resistivity Measurements Electrical World November 18 pp 79 80 Gehlin S E A and B Nordell 2003 Determining Undisturbed Ground Temperature for Thermal Response Test ASHRAE Transactions 109 1 151 156 Gnielinski V 1976 New Equations for Heat and Mass Transfer in Turbulent Pipe and Channel Flow International Chemical Engineering Vol 16 pp 359 368 GS4 Heat Transfer Fluid Fluid Properties 3 Edition CRYOTECH Deicing Technology Fort Madison IA Hooper F C and S C Chang 193 Development of the Thermal Conductivity Probe ASHVE Transactions Vol 59 pp 463 472 Incroper
103. s should check to see that at least one of the temperature limits is reached by the design case Further developments may be forthcoming 2 2 7 Help Clicking on the Help menu item gives the Contents Help on Help and About GLHEPro options Also context sensitive help is provided on the main form In other words if you want more information on any command e g the Select thermal resistance button just click on the question mark button on the right hand side upper corner of the window and a question mark will appear on the cursor Then click on the button and it will display information on the command Selecting the button and pressing the F1 button on keyboard can also do this Contents This opens the User Manual this document to the cover page Help on Help This window gives a brief summary on how the Help controls work in the current release of GLHEPro About GLHEPro This window some basic information on the GLHEPro version number who the current version is licensed to your license number on GLHEPro V4 1 4 and later and copyright information 2 2 8 Adding Notes At some point the user may desire to annotate his or her project To this end there is a notepad of sorts provided within GLHEPro To open it click the notepad button that appears in the menu bar of the main GLHEPro window In the box that appears see Figure 2 37 the user may input an internal name for the project as well as any notes that are
104. sistance may now be estimated more accurately by having GLHEPro determine the convection coefficient for the fluid Gnielinski s correlation 1976 is used for turbulent flow while a linear interpolation between the laminar solution and the value resulting from Gnielinski s correlation at Re 2500 is used for the transition region between Re 2100 and Re 2500 The option of entering a user specified convection coefficient is still available Fluid property routines have been completely revised The user may now specify the composition and concentration of the working fluid This eliminates the need for a library of fixed concentrations although the library remains in case additional fluid types outside those contained within GLHEPro are desired Double U tube and concentric tube heat exchangers have been implemented in addition to single U tube systems These configurations operate exactly the same as the single U tube configuration within GLHEPro Output reporting has been markedly improved The user is now able to specify what information is reported and certain data may be written to a Microsoft Excel compatible CSV comma delimited file if desired G function specifications can now be output in formats usable by both the EnergyPlus and HVACSIM simulation tools Support for the BLAST load analysis program has been dropped The option of adding international ground temperatures for selection is now available Values for the long tim
105. sues with data handling are and 33 3 PROGRAM IMPROVEMENTS The following sections detail the improvements and additional features added to the program during version updates 3 1 Additions to Version 4 1 Significant program changes e Improved transition of g functions from the sort to long time step methods The effects of this change would only been seen in external simulations with time steps on the order of minutes to hours e Improved extrapolation of g functions when B H is large i e very large spacing between boreholes or very short boreholes by approximating B H infinity as the g functions for a single borehole Minor Functionality improvements e New program language solves installation issues GLHEPro will now run when the Regional Language settings use a as a decimal separator without having to change system settings e User specific License CD number and user name are now displayed on About GLHEPro form and program outputs Added Clear and Paste options to Add new heat pump heating cooling data forms Allow heat pump data to be imported from txt files Re enabled basic Help functionality Updated user interfaces Display Reynolds number after resistance calculations Added G function specifications for custom Type 628 file for use with HVACSIM e Improved error handling Library Changes e 361 new heat pump models have been implemented bringing the current total to1202 S
106. t plot Figure 2 29 shows hourly heating loads for a church building with a setback thermostat In this case the peak load could be approximated as being one or two hours in duration However it would likely be useful to review the entire system operation and consider whether turning the system on earlier would allow significantly smaller loads over a longer number of hours and in turn allow for a smaller ground loop heat exchanger The second example Figure 2 30 shows cooling loads for an office building with heavy internal heat gains and a setback thermostat In this case a peak duration of 8 10 hours would likely be appropriate Appendix E describes an auxiliary spreadsheet that assists in determination of the peak load duration 5 n theory this should work with other spreadsheets However it has not been tested 39 Heating Load BTU Cooling Load Wh Church Loads for Birmingham AL 500000 527500 450000 474750 400000 422000 350000 369250 300000 316500 2 8 250000 263750 4 3 200000 211000 2 150000 158250 100000 105500 50000 52750 0 0 0 0 0 09 0 0 0 0 0 0 0 0 0 0 0 140 145 150 155 160 165 170 Time Hours Figure 2 29 Heating loads for a peak day Young 2004 Tulsa Hourly Loads 0 0 5000 17 10000 34 15000 51 amp 5 20000 68 9 25000 85 30000 10
107. t pump models The user library contains all of the custom heat pump data stored by the user For a listing of the new heat pump models in Version 4 0 as well as details on the naming convention which describes the flow rates used to develop the equation fits for the new heat pumps consult Appendix C Select Heat Pump Currently Selected Pump is from Standard library Model Classic Model 030 Cooling Heat of Rejection QC b EFT c EFT 2 KW Power d e EFT f EFT 2 KW 1 079521 d 0 023248 b 0 000621 0 000185 c 0 000016 f 0 000005 Heating Heat of Absorption QH u v EFT w EFT 2 KW Power QH x y EFT z EFT 2 KW 0 644526 X 0 104982 V 0 003129 Y 0 000949 w 0 000016 2 0 000005 QC Cooling load KW kBtu hr QH Heating load KW kBtu hr EFT Fluid temperature entering the Heat pump Export data to HVACSIM 565 parameter file ET Figure 2 21 Select Heat Pump dialog box The Select Heat Pump dialog box also displays the various coefficients of the heat pump selected These default coefficients may be adequate for a quick feasibility study but care should be taken during the final stages of the design process to select or add coefficients for the specific heat pump that you will be using tis common practice to use more than one kind of heat pump in an application served by a single ground loop heat
108. ten re o RE 83 2 Peak Day Determination E eic oido ks eco pq e Odo Di gebe ERE e Que edie 84 2 Parameter Dipl oou ori pe tcd 84 4 Determination of Peaks ino tro Deed ra rans 87 9 Getting Monthly Peak Loads Pen For a a legged ee Pone 92 6 Other ETATE P 94 ACKNOWLEDGMENTS The development of the original version GLHEPro V 1 0 of this software was supported by the National Rural Electric Cooperative Association NRECA and the Electric Power Research Institute EPRI Their support is gratefully acknowledged 1 INTRODUCTION Welcome to GLHEPro for Windows Version 4 1 the professional Ground Loop Heat Exchanger design software GLHEPro for Windows is used as an aid in the design of vertical borehole type ground loop heat exchangers used in geothermal heat pump systems The heat exchanger may be composed of any number of boreholes arranged in various configurations GLHEPro for Windows performs three different tasks e First it allows users to perform a simulation of their ground loop heat exchanger to determine monthly peak and average entering fluid temperatures to the heat pump from the borehole s the power consumed by the heat pump and the heat extraction rate per unit length of borehole e Second GLHEPro for Windows can determine the required depth of the borehole s that will meet a us
109. then press the Paste button to load the data into the form When you have 64 correctly entered the heating performance data your dialog box should be identical to that in Figure A 5 When all of the performance data has been entered correctly press OK The heating mode and cooling mode performance data can also be entered in Metric units if you had chosen Metric Units from the Units menu The coefficients will be displayed with the current unit settings Heating Mode Performance Data EFT Total Heating Heat of Extraction Power Input CF kBtu hr kBtu hr KW 67 46 5 8 71 50 6 0 80 58 65 88 6 9 Figure A 5 Heating mode performance data dialog box View Heat Pump Coefficients Now that we have all of the performance data entered the program calculates the twelve curve fit coefficients To view these coefficients click the View Coefficients button and it will return with a dialog box like that shown in Figure A 6 These are the coefficients that should be displayed on your dialog box Note that these coefficients are dependent on the unit system used GLHEPro automatically converts the coefficients if the units selected changes Coefficients a b c d e and f are for the cooling mode and correspond to the Cooling coefficients shown in Figure Likewise coefficients w x y and 7 are for the heating mode and correspond to the Heating coefficients in Figure A 6 65
110. tion a supplementary spreadsheet is available from Carrier for HAP that assists the user in retrieving the load information needed by GLHEPro In other cases the loads may be typed in manually or may be pasted in from a spreadsheet as discussed in Section 2 2 4 2 Appendix E describes a spreadsheet that takes hourly building loads for the year produces monthly loads and helps determine the appropriate peak duration Monthly direct heating and cooling loads Loads directly on the ground loop heat exchanger not passed through a heat pump may be entered into GLHEPro An example of a direct load would be a system in which cooling is provided by a fan coil that circulates the loop fluid directly through the unit It should be noted that loads should only be entered as either a direct load or as a load on the heat pump However most users probably will not need this option A description of the ground loop heat exchanger This includes the pattern of the borehole configuration or the footprint the borehole radius and the depth of the boreholes if known An example borehole configuration would be 15 boreholes in a 5 by 3 borehole grid GLHEPro for Windows offers approximately 307 different borehole configurations plus the ability to approximate larger rectangular borehole fields In addition to the description of the borehole configuration details such as the heat exchanger type single U tube double U tube or concentric tube heat
111. tton to exit without selecting a heat pump GLHEPro then returns to the Glhepro dialog box and updates the proper lines 22 GLHEPro Main Menu and Toolbar Functions In addition to data entry from the main screen and related dialog boxes GLHEPro has a number of other important functions Most of these are accessible from the main menu and or from the Toolbar as detailed in Figure 2 25 the colored boxes indicate where there are duplicate access methods for a function Many of these are identical to any other Windows application and so are not discussed in detail The rest are discussed in some detail below Toolbar Main Menu GLHEPro default 55 File Units Help Register ZH zW ei zssss zm 2 Figure 2 25 GLHEPro main menu and toolbar with related functions indicated 2 2 1 File Includes the standard file options such as Save Save As Open 2 2 11 Write Current Input Data to File Save This option is used to save all of the input data that is currently entered into GLHEPro to a file that can be retrieved for later use see Section 2 2 1 2 To save your input data choose the Save option from the File menu If there is an input data file Section 2 2 1 3 opened already then this option will save the input data automatically in that input file without bringing up the next dialog box However if there is no input data file open and you want to save the input data in a file or if you choose the Save As
112. types in the user library The user can import soil libraries into the user library when the Ground Properties dialog box is displaying search results however this will effectively click the Show button Import Soil Properties QU GLHEPRO lib 4 Search lib p Organize v New folder z Favorites Name Date modified Type Desktop Downloads Recent Places No items match your search Libraries Documents Music Pictures Subversion Videos T 4 n 7 File name Excel Comma Seperated Values v Open Figure 2 15 Import Soil Types dialog box If the library file being imported contains a soil type that duplicates a soil type from the standard library the read soil type will not be added to the user library If the library file contains a soil type that duplicates a soil type from the user library however the user will be asked for confirmation before overwriting the existing one 2 1 4 Select Ground Temperature GLHEPro provides a U S map that shows the distribution of undisturbed ground temperature on a yearly average basis Figure 2 16a shows the dialog box that allows the user to enter an estimate of the undisturbed ground temperature if the experimental data to calculate it is not available Note that the map is in English units no SI version is available at this time However for conven
113. uilding energy analysis program such as HVAC Load Calculations for Windows or the Trane System Analyzer For instructions on using these programs to generate input files for GLHEPro for Windows see Appendix B If using the Carrier HAP program to generate loads for GLHEPro consult the HAP help file for details on how to obtain the values needed in GLHEPro Using the spreadsheet provided by Carrier the heat pump loads can be copied and pasted as described in Section 2 2 4 2 Selecting this option brings up an Open dialog box see Figure 2 27 to open a file from which the loads are to be read You will then have to select the type of file and file name to be used for reading the loads The type of file can be selected by clicking the second drop down box and choosing one of the file types Once you have selected the file type the dialog box updates with the file names of that type Select one of the files by clicking it You can also navigate to other directories in a manner similar to that used for any other Windows application Click the Open button to confirm your selection or the Cancel button to exit without opening the file containing the loads If reading from a Trane System Analyzer file or an HVAC Load Calculations for Windows file GLHEPro will open the load editing dialog box similar to that shown in Figure 2 28 You can also edit the loads specified in this dialog box Finally click OK to confirm the edited loads or Cancel to
114. ular set of peak durations either enter the durations into the primary input form or enter them directly into the spreadsheet and click the Calculate Peak Responses button The heating and cooling day temperature response graphs will then be updated The normalized temperature responses can peak below one or above one The user is attempting to find the combination of peak load and peak load duration that give a peak normalized temperature response closest to one This combination when used in GLHEPro will give the most accurate estimate of peak temperatures As an example consider a hypothetical office building located in Albuquerque New Mexico The building is significantly cooling dominated as shown by the plot of hourly loads over the year in Figure E0 6 Heating is shown as positive and cooling as negative For this building 87 and location the highest heating and cooling loads are quite easy to spot the maximum heating load is toward the end of December while the maximum cooling load is in early July The loads for the days which contain the peaks and the days immediately preceeding the peak days are shown in Figure E7 heating and Figure E8 cooling Building Load Profile CT ey Load Heating Required Cooling Required Figure E0 6 Albuquerque office building annual heating and cooling loads 88 Heating Load Profile Heating Load Btu h
115. used to enter the borehole configurations physical and thermal properties ground properties circulating fluid and the heat pump Figure 2 1 shows the Glhepro Dialog Box with the default values entered for each item The users may use the default values if appropriate for their ground loop heat exchanger system or they may enter new values for one or all parameters The following list provides a description of each item on the Glhepro dialog box including the appropriate IP English and SI Metric units and the default value that will be used by GLHEPro if new data is not entered GLHEPro default Loads Units Action Help Register Dae S14 amp 6 M s Borehole Parameters Active Borehole Depth 40 ft Select Borehole Borehole Diameter 4 33 in 3607 Fil hr Borehole Thermal Resistance 0 360 Btu hr ft Borehole Spacing 15 ft Thermal Resistance Borehole Geometry LINE CONFIGURATION 3 1 x 3 line Ground Parameters Soil type currently entered Thermal Conductivity of the ground Btu hr ft F Select Ground Parameters Volumetric heat capacity of the ground Btu F ft Select Ground Temperature Undisturbed ground temperature T Fluid Parameters Total flow rate for entire system 31 6404 Select Fluid Fluid Type Pure Water Fluid Concentration 0 Average Temperature 68 F Volumetric Heat Capacity Ibs Btu F f Btu hr ft F Ibm ft h
116. ved Exporting creates a text file with the extension lib containing the heat pump data in a specific format The user can use the export feature only when the currently displayed heat pump is from the user library Select Heat Pump Export the current Heat Pump alone Export all the Heat Pumps of the current Brand Export all the Heat Pumps from the user library Figure 2 24 Select Heat Pump dialog box of the Export feature To use the import feature click on the Import button on the Select Heat Pump dialog box An Open dialog box similar to that shown in Figure 2 15 will appear Select the file that contains the desired heat pump data and press Open Importing reads the lib file created by exporting and stores the heat pump data in the user library You may also import txt files of the same format If the library file being imported contains a record with the same brand name as any one of the records from the standard library the record will be added to the user library with the specified brand name with a 1 appended to the end If the library file contains a record which has the same brand and model names as any one of the current records from the user library the user will be asked for confirmation before overwriting the existing record 34 Once you have completed selecting the heat pump curve fit coefficients click the Select button to confirm your selection or the Cancel bu
117. verwritten if the unit system is changed as these cells are updated when the units are changed Finally the location can be entered in cell E3 however this is just for the user s reference as the program does nothing with this data If the user does not possess the full yearly load profile and instead has design day data or simply wants to test a different day the 24 hourly loads for the day of interest may be manually entered into column B of the Peak Heating Day and Peak Cooling Day worksheets Be sure to make 83 note of the units to ensure compatibility since the temperature response is normalized an error in units will not show up until the monthly peak loads are calculated A B Heating Cooling 1 Date Time delivered delivered 2 Btu h Btu h Location 3 1 1 2002 1 00 0 0 BOK Office Building Albuquerque NM 4 1 1 2002 2 00 0 5 1 1 2002 3 00 0 0 1 1 2002 4 00 7 1 20025 00 0 D Compute Peak Days 8 1 1 2002 5 00 0 0 9 1 1 2002 7 00 0 0 Figure E0 3 Load entry 2 Peak Day Determination Once the loads have been properly entered into the worksheet press the Compute Peak Days button The program will then determine on which days the peak heating and cooling loads occur This is done by finding the days on which the absolute maximum hourly loads occur While it is not necessarily true that the day with the maximum load will also be the day with the greatest temperature deviation it has be
118. with no interior boreholes Click OK to confirm your selection or Cancel to exit without selecting a borehole configuration 19 Select Borehole Configuration Select Configuration LINE CONFIGURATION v Select sub configuration CAPE R 2 1x2 line o o 5 3x3 L config 8 3x3 L2 config 7 3x3 U config o o xw p o 9 3x3 rectangle 8 3x3 open rectangular config Figure 2 9 Borehole Configurations If the user has purchased the option GLHEPro also has the capability of approximating rectangular borehole fields larger than those available with the standard selection of configurations Rectangular fields containing up to 900 boreholes may be selected by specifying a rectangular configuration as the main configuration in the borehole configuration form shown in Figure 2 8a and selecting the Build your own sub configuration option it s the last entry on the list This will bring up the form shown in Figure 2 10 the large rectangular field entry form 20 Define Large Borehole Field Number of boreholes in X dimension Number of boreholes in Y dimension Figure 2 10 Large borehole field entry form After entering the desired number of boreholes in both dimensions the orientation of the layout e g 12 by 14 vs 14 by 12 does not matter and pressing OK the g functions will be computed b

GLHEPro User Manual - Building & Environmental Thermal Systems

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GLHEPro User Manual - Building &amp; Environmental Thermal Systems

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GLHEPro User Manual - Building & Environmental Thermal Systems