Home

Flowan software User Guide - Process Tomography Limited

1. The calculation is carried out for all of the zones in the zone map and all of the frames of data and the results are displayed immediately in the text box as an overall volumetric and mass flow in cm or g assuming that a material density value has been entered in the settings gt correlation menu The flow rates in the individual zones can be displayed via the Settings gt Display menu by setting the Plot scroll box to Flow Rate The flow rates are shown as a violet plot as shown in figure 6 1 1 below Howan v1_20 golfball no session desc BE x File Settings Analyse Help Nu ud L zfvf Fifan Spf Fr Celex Cr psd st en full mk lt 1 672 1 Normalised Concentration Flowrate cm Sec Plane 2 Plane 1 Derived 0 00 0 01 0 00 0 00 0 00 0 469s 27 7 pk 0 082 fms 93 8 Volumetric flow 57 cm 3 Mass flow 33 g Volumetric flow 57 em 3 Mass flow 33 g Volumetric flow 57 cm 3 Mass flo 339 Volumetric flow 57 cm 3 Mass flow 33 g Yv Figure 6 1 1 Flow rate plot for central zone 22 xxx Note that in this modse of operation the Flowan software shows the overall frame flow rate irrespective of which zone is selected The overall flow reported in the text box in figure 6 1 is 57cm or 33 g which aproximates to the nominal volume and mass of the golf ball used in the experiment 63 cm 36g However it is possible to increase the accuracy of the flow rate calculation by correct
2. 0 25 0 2 270 0 15 No Oo Speed cm Sec 250 240 230 0 1 0 05 Normalised Concentration 0 05 0 1 6 6 5 i 7 5 6 6 5 g 9 5 10 10 5 11 Time Sec Plane 2 Plane 1 Derived 0 10 0 10 0 03 0 22 0 06 0 053s 246 9 pk 0 662 fms 10 5 Elec 8 Meas 28 Frames 2631 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 2631 ave rate 200 fps A 8 2 4 Zoomed Data 8 4 CALCULATING THE VELOCITY AND FLOW DATA From figure 8 2 4 it is clear even from the apparently semi random concentration measurements that the data in Plane 1 green leads that in plane 2 red In fact the data is relatively well correlated as can be seen by clicking the mouse cursor in the data at various time points and examining the correlogram for a range of zones Now click on the All button to analyse the data to produce the velocity and flow information The velocity in the centre zone will be displayed as shown in figure 8 2 5 By clicking on the zone map to select a range of zones explore how the particle velocity changes over the tube cross section It is highest at the centre of the tube and reduces towards the walls as expected for this type of flow Note that the text box gives the overall flow of materials as 927 cm 35 Howan v1_20 gravityflow no session desc Nof taf Zr vif rifal sp Feces cr psd _stfen tulle lt gt Figure 8 2 5 Vel
3. 4 3 1 Flowan window for golf ball data ball inside sensor display zoomed The passage of the ball through the sensor can now be seen much more clearly as the green and red concentration plots show Note that the display can be unzoomed by right clicking on the upper window and selecting Zoomout 15 4 4 USE OF CONTROL BUTTONS TO DISPLAY CONCENTRATION DATA As an alternative to the use of the menus much of the program functionality can be controlled using the buttons located on the Toolbar located underneath the menu bar The buttons which control the display of concentration data are listed below Nw Ld rL Zr St En ful Mk The New button has the same effect as using the File gt Reset menu sequence which removes all of the loaded data from memory It is not necessary to use this button before loading new data if the previously selected zonemap is to be re used The Load button has the same effect as using the File gt Load menu sequence The Reload button reloads data for the previously loaded data file It allows the original data to be reloaded without having to reselect the zone map 1f the current data file has been modified This applies a correction for zero drift in a similar manner to that implemented by the Settings gt zero menu sequence The parameters used are those defined in the Zero Settings data window See section 7 2 for additional information This button defines the current cursor position on
4. 6 cm 3 s Volume 2025 cm 3 Min Shisha Wa Y axis lower l Mass 1 29 KO 15 47 20 49 50 Time axis f ini Zeid Zero size Online Time 22 04 UnAce 0 5 Working 5 e T ouan time Tansa T ea lation engine status status stamp and speed resolution Plot selection Figure 10 6 1 The FlowanRT window The FlowanRT window contains a number of real time values a time series plot of one or more of these values and a status area as shown in figure 10 6 1 above More detailed information about the FlowanRT window is given in section 10 9 43 10 6 2 SETTING UP FLOWAN RT In the FlowanRT window Select tick the Holdup Concentration box and unselect all of the remaining boxes Set the upper holdup limit to 10 box at top right of window and the lower limit to 0 box above Set button by typing the required values into the upper and lower y scale limit set boxes Confim these values using the Set button The FlowanRT window should be similar to that shon below in figure 10 6 2 V Holdup 0 63 Ho T Ave speed 0 0 cm s FlowRate 0O 0 1 cm 3 s l Volume 1088 8 cm 3 mo al e Set_ Mass 620 6 g 20E 1207 hoo M InitZera Zero Online Time 13 14 Finished Figure 10 6 2 FlowanRT window holdup settings Now unselect the Holdup box and select the Ave Speed box Set the upper speed limit to 500 cm S and the lower limit to O cm S by typing the required values into the upper and lower y scale limit set
5. Cancel Figure 7 2 1 Zero settings window 26 Set the From box to start set the start time box to 0 seconds and set the Length box to 4 seconds Click on the Zero button then Click on the Close button to exit the Zero settings menu All of the data will be auto zeroed based on the data in the first 5 seconds of the data file and the efects are shown in figure 7 2 2 below Hlowan v1 20 golfball no session desc BEES File Settings Analyse Help Nwaj zivij rifau sp Fr cplex cr psd st en tul mk lt gt 7 019 0 1 500 A 3 0 06 0 04 0 02 0 Normalised Concentration Speed cm Sec Plane 2 Plane 1 Derived 0 00 0 00 0 00 0 01 0 00 0 8 0 6 0 4 0 2 0 2 0 126s 103 3 pk 0 089 fms 25 2 Elec 8 Meas 28 Frames 1823 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps al Figure 7 2 2 Flowan screen following zeroing based on first 5 seconds of data Comparison between figures 7 1 2 and 7 2 2 shows that the sets of data for each measurement plane are now fairly well superimposed figure 7 2 2 whereas previously figure 7 1 2 there was a positive vertical offset between the plane data green and the plane 2 data red 21 7 3 THE RECONSTRUCTION MENU The Reconstruction menu which determines how the permittivity image is calculated is displayed by clicking on Settings gt Reconstruction an
6. Derived 0 07 0 06 0 06 0 10 0 06 0 009s 1523 3 pk 0 789 fms 1 7 Elec 8 Meas 28 Frames 2623 ave rate 200 fps Loading Capacitance file Elec 8 Meas 28 Frames 2204 ave rate 199 fps al Figure 1 1 A Typical Flowan screenshot Detailed information about the operation of the Flowan software is given in the Tomoflow User Manual This additional Flowan User Guide is intended for new users of the Tomoflow R100 system and demonstrates some of the most important aspects of the Flowan software by the use of two example data files which are supplied with the Flowan software The remaining paragraphs in this introductory section describe some background information about the way the Flowan software operates and should be read carefully before attempting to use the Flowan software for the first time 1 2 USE OF MATLAB SCROLL BOXES Flowan is a Matlab program and is controlled by a Windows style user interface However Matlab user interfaces operate slightly differently from standard Windows user interfaces particularly in the way options are selected in Matlab scroll boxes This section describes how to use Matlab scroll boxes fer settings From Start Length 5 Set ero Close Cancel Figure 1 2 A Matlab window containing a scroll box The From box in figure 1 2 above is a scroll box In a scrollbox parameters are selected by left clicking the mouse on the up down arrow buttons at the RH side of
7. and flow are zero at the end of data streaming these values will also be zero in the Flowan RT window at the end of data streaming The volume and mass flow figures are the integrated flows over all of the data frames on a rolling basis The final figure reported 1s the total flow 10 9 FURTHER INFORMATION ABOUT THE FLOWAN WINDOW The time series plot can display a selectable number of the realtime values which are selected using the plot selection check boxes as described in section 10 6 2 The y axis limits are also configurable but only when a single plot is selected The Set button not enter is used to confirm the data for each setting A scroll bar is located underneath the plot and facilitates viewing of the data after streaming has finished Under the scrollbar there are two numbers which indicate the time at the left and right extremes of the plot 45 If the initzero box is checked a zeroing operation is carried out every time FlowanRT starts This is similar to the zeroing operation in Flowan but is always carried out for a fixed period 400 frames or 2 seconds 200fps one window length after streaming commences This is a useful option for lean flow conditions as it removes calibration or drift errors which would otherwise integrate into a flow error over the flow period These errors can dominate the flow figures for lean flow conditions The following points should also be noted 1 The real time figures are corre
8. first move the time cursor to a position where an image of the ball is displayed as a circular ECT image at either plane 1 or plane 2 Now select Settings gt display and use the scroll box to set a new image gain of 5 Click on the OK button and the change in the circular ECT image will be obvious Note that the concentration scale in the upper window and the concentration values in the lower ECT images remain unchanged Ths facility is useful for displaying ECT images at weak concentration levels Reset the image gain to in the image gain scroll box 7 2 ZERO OPTIONS All measurement systems are subject to drift and offset problems to some extent and ECT measurement systems which attempt to measure very small changes in capacitance values are particularly prone to these types of problem A good example can be seen in figure 7 1 2 where the centre zone shows finite offset shifts in the time periods where there is no ball inside the sensor The zero option facility allows users to apply a compensating zero offset to minimise any residual offsets in experimental data where it is known that the signal should be zero The use of this option can be demonstrated as follows Select the centre zone and ensure the data display is unzoomed The Flowan window should ressemble figure 7 1 2 Select Settings gt Zero The Zero settings window shown in figure 7 2 1 below appears fer settings From Start Length 4 Set ero Close
9. idea to save an additional custom configuration file with a unique file name each time the program is run for a new set of input data This ensures that the data can be re processed using the optimum parameter set 2 SETTING UP THE FLOWAN SOFTWARE 2 1 STARTING FLOWAN Open the ECT program group window by double clicking on the ECT program group icon on the PC desktop Then double click on the Flowan icon in the ECT program group window The startup Flowan window similar to the one shown in figure 2 1 below will appear Howan v1 20 golf ball no session desc File Settings Analyse Help Nuf Lajf 2r vif rifa spl Frfcp ex cr psd st en ful mk lt gt 0 1 2 3 4 5 6 f 5 a S ao N OO WO Saree 0 N en se oO poy nN correlation ta fer f Normalised Concentration i f M to SE ho to 0 1 0 1 Time ae 6 T 6 9 Derived Plane 2 Plane 1 Figure 2 1 Blank Flowan window The top window is shown blank in figure 2 1 above but in practice may display some experimental data if a data file was loaded during previous use of the software Select File gt Reset to clear any previously loaded data The Flowan window should now revert to that shown in figure 2 1 2 2 DETAILS OF EXAMPLE DATA FILES The operation of the Flowan software will be demonstrated initially using a set of test data generated by dropping a thin walled plastic ball of OD 50mm filled with polypropylene bead
10. the Data display window to be the start point of the zoom settings This function may also be implemented using Settings gt Display gt Zoom position or from Start point on the context sensitive menu obtained by right clicking on the Data display The start time cursor is displayed as a vertical green dotted line This button defines the current cursor position on the Data display window to be the end point of the zoom settings This function may also be implemented using Settings gt Display gt Zoom position or from End point on the context sensitive menu obtained by right clicking on the Data display The end time cursor is displayed as a vertical red dotted line This button shows the full unzoomed data set in the Data display window This function may also be implemented using Zoomout on the context sensitive menu obtained by right clicking on the Data display This button shows the zoomed data set in the Data display window This function may also be implemented using Zoom on the context sensitive menu obtained by right clicking on the Data display This button reverts to the previous zoom position on the Data display window set through the use of the ful or Mk buttons This button reverts to the next zoom position on the Data display window set through lt The operation of the remaining control buttons is given in section 6 2 and further more detailed information about the functions of all of the control buttons is given in the Tomo
11. vertical axis 3 2 THE STATISTICS WINDOW The lower left hand window is the Statistics display which can show either a correlogram or the power spectral density for the data centred on the frame selected at the cursor point as shown in figure 3 2 below Dg DE Od g a fh OSs 238 5 pko B50 tre 11 0 Figure 3 2 Statistics display in correlogram mode 11 3 3 CIRCULAR IMAGES Four circular images are located under the data display window and are shown in figure 3 3 below Derived 0 00 iets iit Zone Map Derived image Plane 2 imagePlane 1 image Figure 3 3 Circular images Details of the images from left to right are as follows Zone map The zone map shows the electrode locations around the outside of the capacitance sensor together with the zone locations inside the sensor Data for individual zones or the inter electrode capacitances can be selected and displayed by clicking the mouse on the required zone Derived image Displays selected zone based data concentration velocity or flow rate over the time period displayed in the upper Data display window Note that image is displayed using a colour scale where largest pixel value is red and smallest values as blue Plane 2 image Displays pixel based concentration image for plane 2 at cursor point Plane 1 image Displays pixel based concentration image for plane 1 at cursor point 3 4 TEXT AREA An additional text box window for messages and add
12. 2 4 LOADING THE CONFIGURATION FILE Now load the configuration file which was generated for the sample golfball data file by selecting the File gt Load configuration file sequence and selecting the golfball ini file This file is in the c flowan datafiles examples folder An updated Flowan window containing the captured data flow data will appear as shown in figure 2 3 5 2 5 INITIALISING THE FLOWAN WINDOW Left click the mouse in the upper window between the peaks of the green and blue plots at a time around 5 9 seconds The Flowan screen changes to that shown in figure 2 5 1 below Flowan v1 21 no session desc BEE File Settings Analyse Nu Laj e SEFT Sp Fr Cp ex cr psd StfEnffufmk lt 1 5 900 500 0 9 Ja g 0 8 400 207 350 w oe 5 06 300 g 2 A 6 05 aoe p5 LS amp O04 200 2 E k E03 150 0 2 100 0 1 50 0 0 0 1 2 3 4 5 6 r 8 g Time Sec l Plane 2 Plane 1 Derived 0 00 0 03 0 47 0 00 0 00 ffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps E Figure 2 5 1 Flowan window for golf ball data at 5 905 seconds 2 6 USE OF FILE RESET LOAD RELOAD MENU FUNCTIONS The image sequence described in section 2 3 will be displayed if the File gt Reset sequence was implemented as described in section 2 1 However if this sequence is not implemented the data file is loaded directly and images 2 3 2 to 2 3 4 are not displayed when either the File gt load or File gt Reload sequenc
13. 46 4 pk 0 891 fms 10 6 Contents of capture mode buffer m Elec 6 Meas 26 Frames 1285 awe rate 200 fps E Figure 7 4 2 Data window showing constant velocity of 1000cm S To analyse the flow using this constant velocity first click on the Zr button to zero any residual offsets in the concentration plots details in section 7 2 and then click on the FI button to analyse the flow details of which will be displayed in the text area Note Do not use the All button as this will over ride the constant velocity setting and will calculate the flow by deriving the velocity from the concentration plots using correlation in the normal way 7 5 CHANGING THE SENSITIVITY AND ZONE MAPS The method for changing the sensitivity and zone maps used for reconstruction is as follows 1 Copy the required sensitivity map to the Flowan smaps folder 2 Select the Settings gt Sens maps menu option The Sensitivity maps window will appear as shown in figure 7 5 1 3 Type in the relative address of the new sensitivity map against the sensor type in use In the example in figure 7 5 1 the new map for an 8 electrode 28 meassurements sensor has the name Sintef8_32 sif Note that in the measurements column in figure 7 5 1 15 corresponds to a 6 electrode sensor 28 to an 8 electrode sensor and 66 to a 12 electrode sensor 30 Sensitivity maps Measurments Filename Ok Cancel Figure 7 5 1 Sensitivity map window Once the sen
14. 8228g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_TR_m3_loose_full bcp vol 28236cm 3 mass 28236g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Figure 9 3 Typical set of output data in batch mode For further information about the use of the Flowan software please refer to the Tomoflow User Manual 38 10 FLOWAN RT 10 1 INTRODUCTION FlowanRT Flowan Real Time is an additional real time component of the Flowan software suite It operates on data streamed from the ECT32 software and allows live or captured ECT data to be processed and displayed in real time FlowanRT calculates speed flow rate and accumulated volumetric and mass flow online and enables the Tomoflow R100 system to operate as a real time flow meter FlowanRT is supplied as experimental software as it is still under development at present FlowanRT uses the same algorithms as the standard batch mode Flowan software but is a separate application In principle the accuracy should be similar to that of the Flowan software when run on a modern fast PC However as FlowanRT runs in real time under the MS Windows operating system small errors may be introduced because of the way in which the operating system software interacts with the FlowanRT software This will become apparent if FlowanRT is used repetitively to analyse the same set of streamed captured data The FlowanRT software operates as follows The Flowan software is used initially to set up the op
15. Continuous correlogram generated by curve fitting A1 2 2 Effect Of Width of Correlation Window The width of the correlation window determines the time constant of the velocity measurement and the quality of the correlation The correlation window must be always be larger than the transit time of the flow between the 2 measurement planes but see note A1 6 If the two sets of measurements are poorly correlated ie the correlated uncorrelated signal ratio is low then increasing the width of the correlation window will improve the amplitude of the correlation peak in the correlogram An example is shown in figure 4 below for the same data processed with a narrow correlation window red and a wider window blue 4 sec window 0 4 sec window 0 0 0355 Figure 4 Effect of changing width of correlation window The wider correlation window improves the amplitude of the correlation peak relative to the rest of the correlogram values but also increases the measurement time constant reducing the ability to see rapid changes in velocity 49 A1 3 APODISATION It is well known that the use of a correlation window of finite width can cause problems if there are major changes in the data sets to be correlated near the ends of the correlation window A typical example would occur when a slug is artificially truncated in one of the two time variant functions by the correlation window In this case the truncated edge in one function would be incorr
16. ITIALISING FLOWANRT Start FlowanRT by clicking on the FlowanRT icon in the ECT Software group window 39 H9 HowanRT Figure 10 4 1 The FlowanRT window The FlowanRT window will appear as shown in figure 10 4 1 above and the Flowan ini configuration file will be loaded automatically Now temporarily minimise the FlowanRT window to the Windows Task Bar 10 5 INITIALISING ECT32 Start ECT32 and set up the Configuration window as shown below Select the example data file gravityflow bcp which is in the Flowan datafiles examples folder and use the ssm8_32 sif sensitivity map ESE Configuration Window E M Hamen M ete w HetiersensarpaneTs curentii Gell heen wowe SSS Figure 10 5 1 ECT32 Configuration window 40 Click on the Setup System button The main ECT32 window will appear Check that the example data file data plays back correctly in ECT32 by selecting Playback mode and replay the data using the forward play gt button in the ECT32 Control Panel Set ECT32 to Idle mode by clicking on the Idle mode button in the ECT32 control panel Now adjust the ECT32 window so that it appears as shown in figure 10 5 2 with only the upper circular images and the ECT Control Panel displayed To do this ensure that the ECT window is in the Restore Down mode single square only displayed in the top RH corner of the window next to the close X box Use the mouse to drag the top section of the ECT image window to reduce
17. If the length between the centres of the measurement electrodes is L and each set of measurement electrodes is of axial length l then for any approximately spherical feature of the same scale as the pipe diameter D the time t taken from first arrival at the first electrode to departure from the second is given by the equation t V L 21 D 5 5I In practice V L 21 D is about twice the nominal transit time though it may be more depending on the sensor geometry Equation 5 assumes the largest flow structures are at the pipe diameter which is reasonable for many flows but not necessarily so for coherent slug flows Although apodisation itself does not widen the peak a wider correlation window is normally used when apodisation which is almost always used is applied and this will widen the correlation peak Apodisation is part of the need to have correlation windows much greater than the transit delay see below Using apodisation means that the minimum effective window width is doubled So allowing an increased window width of 2x for flow structures and 2x for apodisation means that the minimum realistic correlation window width is 4x the nominal value As typical flow patterns are Statistically variable in practice even wider windows are found to be necessary up to 20x the transit time However this will clearly have an adverse effect on the ability to see rapidly changing velocities In general the use of wider correlation windo
18. TOMOFLOW FLOWAN USER GUIDE Software version 1 33 Issue 2 May 2006 Tomoflow Ltd 86 Water Lane Wilmslow Cheshire SK9 5BB United Kingdom 44 1625 536672 enquiries tomoflow com i CONTENTS Summary of changes made since v1 21 Introduction 1 1 Overview 1 2 The use of Matlab Scroll boxes 1 3 Software instruction conventions 1 4 The Flowan configuration file Setting up the Flowan software 2 1 Starting Flowan 2 2 Details of example data files 2 3 Loading a data file 2 4 Loading the configuration file 2 5 Initialising the Flowan window 2 6 Use of the File Reset Load Reload menu functions 2 7 Configuration file status following installation of a new version of flowan Overview of Flowan window 3 1 The Data display window 3 2 The Statistics window 3 3 The Circular images 3 4 The text box Viewing concentration data 4 1 Identifying plotted concentration data 4 2 The basic screen functionality 4 3 Zooming the display 4 4 Use of control buttons to display concentration data Viewing velocity data 5 1 Calculating the golf ball velocity 5 2 Correlation considerations 5 3 Correlation tips and hints 5 3 1 Setting the time limits for analysis 5 3 2 Defining the flow direction and velocity convention 5 3 3 Determining the direction of flow 5 3 4 Setting the displayed speed limits 5 3 5 Additional information 5 4 Use of the velocity test data file 5 4 1 loading the data 5 4 2 analysing the data Vie
19. a basic analysis has been caried out using this reference configuration file users should modify the parameters using the settings menu to optimise the data being analysed and then save the optimised settings parameters to a new configuration file name file gt Save confige gt filename ini for future use 10 3 OVERVIEW OF THE FLOWAN WINDOW The Flowan window is divided into a number of component parts consisting of a large upper Data Display Window together with a statistics window and a set of 4 circular images located below the upper Data display window A text box is located at the bottom of the Flowan window 3 1 THE DATA DISPLAY WINDOW o S g mam y oo O yas Speed em Sec i Normalised Concentration Oo wm 0 2 Time Sec Figure 3 1 Data display window The upper Data Display window shows zone based time related data which can be concentration velocity and or flow rate Data for individual frames for display in the lower windows can be selected with a mouse or keyboard controlled time cursor When a new data file is loaded the data for Zone 1 is displayed by default In the normal mode of operation time is displayed along the horizontal x axis concentration is displayed along the LH vertical y axis and Velocity speed is displayed along the RH vertical axis Alternative options allow inter electrode capacitances to be displayed along the LH vertical axis and Flow rate along the RH
20. a large extent on the width of the correlation window selected Further detailed information about correlation techniques can be found in Appendix 1 18 5 3 CORRELATION TIPS AND HINTS When the Analyse menu is used to generate velocity and flow rate data the correlation calculation is carried out using the parameters defined in the correlation settings window shown in figure 5 3 1 below This window is diplayed using the Settings gt correlation menu sequence Correlation settings Sensor length 14 Pipe diameter 53 Density js Units length mass fom fo Speed limits a 1000 Only seek valid speeds Speed resolution 5 Window fi Minimum correlation pz Max find mode pol Plane 1 leads E Concentration source POP Correlate differential E Normalize corelogram fy DE Correlate zoomed only f Hold window Apodization function rl il Il Ok Cancel Figure 5 3 1 Correlation settings window 5 3 1 SETTING THE TIME LIMITS FOR ANALYSIS All of the frames in the loaded bcp data file are analysed to produce the velocity and flow data unless the Correlate zoomed only box in the correlation settings window is ticked In this case only the data between the start and end points of the zoomed data is used for the correlation calculations 5 3 2 DEFINING THE FLOW DIRECTION AND VELOCITY CONVENTION If the Plane I leads box is checked the velocity is defined to be positive if the flow is from plane 1 to
21. ated Now click on the rL button to re load the experimental data and select the centre zone The modified Flowan window is shown below Howan v1 20 golfball no session desc lel x File Settings Analyse Help No Lajf 2r vif rian Sp Frfcpfex cr psd _st en full mk lt gt 7 019 ai 500 Normalised Concentration 0 1 2 g 4 5 6 fe 8 g Time Sec Plane 2 Plane 1 Derived 0 00 0 00 0 00 0 01 0 00 0 126s 103 3 pk 0 089 fms 25 2 Elec 8 Meas 28 Frames 1823 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps E Figure 7 1 2 Flowan window using modified concentration scale 29 Figure 7 1 2 shows the concentration plotted over a more restricted range and it now is possible to see the ECT measurement noise This applies particularly when the centre zone is selected as shown in figure 7 1 2 as this is the zone where the ECT noise levels are highest This can be confirmed by clicking the mouse to display the concentration signals in some of the other zones in the zone map Figure 7 1 2 shows up a measurement problem as there is a slight zero offset between the measurement data for the two planes and this will be discussed further in section 7 2 7 1 2 Gain of circular ECT images The gain of the displayed circular ECT images can be changed from its normal value of 1 using the image gain scroll box To show the effects of this
22. ax find mode Flowrate windo Flane 1 leads Leth asis grid Aiii TATE Right asis grid Concentration source Correlate differential Est limits image limits Normalize corelagram 0 005 Estemal data limita Correlate zoomed only External data corr zone Hold window i External data mult offset Apodization function ae Measurmnents From a 25 Aamaps esmi_ 3 sif Start o 6 Asmapsssml2 32 sif Length i 15 a Asmapsssmb 32 sit Set ero Close Cancel Cancel Reconstruction settings ES 13 Model maze pa K 1 16 z foo rot a 1 19 Gain 2 ae A O Iterations T Lot Loto e at Image truncation O4 1 4 26 27 5 z 28 Invert normalisation Invert 30 FResample 12345 67 8 9 1011121314151617181920212223242526272829303132 Mode EPE Zone j area Joad zone save zone Finish Cancel APPENDIX 3 FLOWAN PARAMETER LIST The following is a list of the parameters used in the Tomoflow User Manual A Al Cmax Cmin Cl C2 Kl K2 Le Lf Lg Lm Ls ql q2 Cross sectional area of flow cross sectional area of ith zone maximum inter electrode capacitance which can be measured by ECT system minimum inter electrode capacitance which can be measured by ECT system concentration in zone plane 1 concentration in zone plane 2 pipe diameter normally Ds flow diameter of sensor contents internal diameter of s
23. boxes Confirm these values using the Set button The FlowanRT window should now ressemble that shown below in figure 10 6 3 l Holdup 0 63 500 V Ave speed 0 0 cm s FlowRate 0O 0 1 cm 3 s l Volume r 1088 8 cm 3 m l al gt o Segt Mass 620 6 q 12 07 12 07 fico intem ero Online Time 13 14 Finished Figure 10 6 3 FlowanRT window Speed settings 44 Now re select the Holdup box The upper set box will be greyed out and the lower set box now determines the horizontal axis display time in seconds Enter 10 S into the lower limit box and confirm this value using the Set button The FlowanRT software is now set up to receive streamed data 10 7 STREAMING THE DATA In the ECT32 Control Panel window select Playback mode and then click on the forward play button Data will be streamed and displayed to the FlowanRT window as shown in figure 10 7 1 below f HowanRT Standby M Holdup 0 61 V Ave speed 0 0 cm s FlowRate 0 0 1j cm 3 s l Volume 1088 8 cm 3 in l Mass 620 6 q T gt I InitZero Zero o nline Time 1 3 15 Finished Figure 10 7 1 FlowanRT window showing streamed data 10 8 INTERPRETATION OF DATA In figure 10 7 1 the Red trace is the average Concentration Holdup per frame inside the sensor and the Green trace is the average velocity speed per frame inside the sensor The figures for Holdup Average speed and FlowRate are instantaneous values If the Holdup
24. correlation A1 7 Correlation window size A1 8 Calculation of flow Appendix 2 Parameter settings in Refconfig ini file Appendix 3 Flowan parameter list 1 INTRODUCTION 1 1 OVERVIEW Flowan is an off line program which processes capacitance data captured using a twin plane ECT sensor and measurement system such as the Tomoflow R100 PTL300E equipment to produce velocity and flow profiles and overall flow data for a mixture of 2 dielectric materials Flowan generates instantaneous concentration profiles of the flow inside the ECT sensor at two axial measurement locations planes for each frame of capacitance data These concentration profiles can be calculated for a relatively small number typically 13 of user defined zones in the flow cross section Cross correlation techniques can then be used to derive the instantaneous velocity in each zone from the concentration profiles at the 2 measurement planes The overall flow profile can also be calculated from the concentration and velocity profiles The Flowan software displays very detailed informaton about the flow structure in both numerical and graphical formats A typical Flowan screen is shown in figure 1 1 below Howan v1 20 sw1_0 File Settings Analyse Help Nef La rh 2r vif Fifan sp Fr Cefex Cr psd stem full mk lt gt 0 3 0 25 0 2 0 15 0 1 Speed cm Sec 0 05 Normalised Concentration Oo hpl ee ged it 0 05 0 1 Plane 2 Plane 1 4
25. ct at the time displayed by the time axis upper limit There will always be a delay of one window length between the real time data and the input stream this is a natural consequence of the algorithm used in FlowanRT 2 The units and displayed resolution number of decimal points can be set in Flowan using the Settings gt Display menu sequence 3 Holdup is the concentration or volume ratio averaged over all of the zones 4 The Average speed is calculated from data for zones with valid velocities only 5 The Flowrate is calculated from data for zones with valid velocities only If the flowrate window set in Flowan gt Settings gt Display is greater than zero a second figure in brackets indicates a rolling average over this window 6 Volume is the Volumetric flowrate accumulated from the start of data streaming 7 Mass is the Mass flowrate accumulated from the start of streaming 10 10 TO PROCESS ANOTHER DATA FILE Set the ECT32 software to Idle mode This will reset the ECT Control Panel playmarker to the start of the currently loaded data file To replay and process the existing loaded data file set ECT32 to Playback mode and start the data playback FlowanRT will automatically reset and will process the new set of streamed data Alternatively load a new data file to ECT32 This new data file can then be streamed to FlowanRT in a similar manner lt NIB If attempts are made to play back the data file backwards th
26. d is shown in figure 7 3 1 Model K Esold Gain Iterations T Image truncation O4 14 Invert normalzatiom Insert Resample 200 CK ineansation M Fick Coeff tile cktestcoetf mz k Cancel Figure 7 3 1 The Reconstruction window Details of the Reconstruction parameters with suggested default values where appropriate are as follows 1 Model The concentration permittivity model to be used Parallel Series or Maxwell 2 K The ratio gt 1 of the permittivity of the mixture at the lower and upper permittivity calibration points 3 Ksolid The ratio gt 1 of the bulk solid permittivity of the two materials in the mixture Note for a liquid gas mixture Ksolid should be set equal to K 4 Gain 1 The feedback gain used in the iteration algorithm 5 Iterations 0 The number of iterations used in the iteration algorithm To set no iterations equates to simple LBP reconstruction set Q 6 Image truncation Calculated pixel values outside the set range will be truncated to have the values set in the image truncation limits boxes This allows physical limits to be set to limit the allowable pixel values Confining these values between 0 and is physically realistic but may not always be optimum Because ECT is an approximate imaging technique the pixel and hence zone values may fall outside the nominal range of O and 1 even though the average for the image as a whole may be correct Limiting th
27. e 13 155sec 1 00 Model Series 1 00 K 1 60 Gain 1 00 Offset 0 00 Yol Ratio 1 18 0 0 00 System Disabled Calibrated None Frame Info 2632 13 155sec 200 0 200 0 ps 7 Plane 1 frame 2632 time 13 155sec 1 00 100 0 0 00 Displaying from file gravityflow bep Model Series K 1 60 Gain 1 00 Offset 0 00 Yol Ratio 0 50 Mode apture Record Playback I Autostop rom Kf lt sto gt gt Holdup Ave speed 0 0 V FlowRate 0 0 0 ns Idle Inactive M vol d M olume Framerate Set fioo Actual 200 0 interval msec 10 x zi gt _Set_ iE Mass 0 0 Of5 0 Buffer lenath Frames 1000 Time sec 10 00 Load Gave T InitZere Zero Offline listening on port 3001 Orj Dew i AutoShapes a LIOE 4l ee DEI o AA Ege Page 3 Sec 1 3 4 At 15 icm Ln 3 Col 83 REC TRK EXT OVR English U K Stat S GS GB Outbor Outlo EE 2 Microsoft ECT Software ECT32v2 AowanRT RowanRT am Ea YO 5 RD 11 24 Figure 10 5 3 Adjusted ECT32 and FlowanRT windows In the FlowanRT window note the FlowanRT listening port number displayed in the connection status box lower left hand box at bottom of FlowanRT window This will typically be 3001 unless other software has already claimed that port In the main ECT32 window open the ECT32 network connection dialog window File gt Remote data streaming T
28. e pixel values to 0 and may lose useful correlatable structure from the signal cause the speed estimation to be degraded Limits of 0 4 and 1 4 are sensible common values 28 7 Invert normalisation Normally the concentration data is displayed as the fraction of high permittivity material present in the low permittivity material as calibrated In this case the calculation of flowrate volumes and mass will then be that of the higher permittivity material If the flowrate of the low permittivity material such as bubbles in a liquid is required the concentration parameter needs to be inverted s that O corresponds to the high permittivity material and 1 corresponds to the low permittivity material Pressing the Invert button initiates this inversion while pressing Invert again reverses back to the standard concentration convention 8 Resample In units of frames per second fps If this button is clicked the set of measured capaciance data is re sampled at the rate displayed in the box The number displayed in the box by default is the average for the data set but a different number may be entered if appropriate This feature may help in certain circumstances primarily because inherent limitations in the Windows operating system mean that data is not necessarily evenly spaced in time This correction is not normally necessary with the newer DAM200E capacitance acquisition module 9 C K Linearisation If this option is checked the sen
29. ec The velocity in other zones can be displayed by clicking on the required zone in the zone map In this case as there is a single object all of the zone velocities are similar Note that the velocities in each zone for each frame of data are stored in a temporary file so that they can be displayed as required and also used in any calculations of flow or flow rate see section 6 17 5 2 CORRELATION CONSIDERATIONS It is important to understand that the velocity can only be calculated if there is correlatable data present This can be demonstrated by un zooming the upper window display right click and select Zoomout where the results are shown in figure 5 2 1 below Hlowan v1 21 golfball no session desc BEES File Settings Analyse Help Nu id zivij rifau sp Fr cplex cr psd st en tul mk lt gt 1 D T Normalised Concentration Co Co in Speed cm Sec Uo w 0 1 i Plane 2 Plane 1 Derived 0 00 0 01 0 00 0 00 0 00 Elec 8 Meas 28 Frames 2631 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps A Figure 5 2 1 Unzoomed Flowan screen showing velocity plot In this case the blue velocity plot only exists for a short time period during the passage of the ball through the sensor measurement planes Outside this period there is no correlatable data The period for which the velocity plot exists depends to
30. ectly correlated against the real edge in the other function To overcome this problem the data within the correlation window is normally weighted to give more prominence to the data close to the centre of the window by tapering the data smoothly down to zero at the edges of the sampled region window This weighting process is known as apodisation and there are a number of weighting functions which are commonly used for this purpose including Cosine and Hanning The weighting is applied to each of the constituent concentration profiles C t and C t before they are correlated Apodisation suppresses spurious peaks which would otherwise be produced in the correlogram One of the effects of apodisation is that a somewhat wider window is needed to get the same effective window length It also removes artefacts such as the velocity apparently increasing exponentially as it would otherwise do in the above example A1 4 NORMALISATION OF CORRELATION COEFFICIENTS The correlation factor R t is normalised so that its maximum value is 1 for perfect correlation whatever the amplitudes of the time variant signals functions As we need to introduce the concept of autocorrelation for this normalisation process we will modify the terminology used so far to avoid confusion The correlation coefficient between 2 different functions 1 and 2 will be written as R12 whereas the correlation coefficient between 2 identical functions autocorrelation will be wr
31. en the two measurement planes which are separated by a distance of 13cm 33 8 3 VIEWING THE CONCENTRATION DATA Use the Zoom controls to display the main region of flow as follows Left click in the Data display window at a time around 6 seconds and then click the St start zoom button Left click in the Data display window at a time around 11 seconds and then click on the En end zoom button Finally click the mouse cursor in the centre of the flow data at a time around 8 5 seconds The Flowan screen should now resemble that shown in figure 8 2 3 below Howan v1 20 gravityflow no session desc BE Es File Settings Analyse Help Nef Ld iL Z vif rija Sp Fr Cplex Cr psd st en full mk lt gt 0 3 8 390 0 25 0 2 0 15 0 1 250 Speed cm Sec 0 05 Normalised Concentration ok 0 05 0 1 6 Time Sec Plane 2 Plane 1 Derived 0 05 0 10 0 03 0 22 0 06 0 053s 246 9 pk 0 662 fms 10 5 Elec 8 Meas 28 Frames 2631 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 2631 ave rate 200 fps E Figure 8 2 3 Flow data with zoom points set Now click on the Mk Zoom in button The screen changes to that shown in figure 8 2 4 and shows the flow of beads on an expanded time scale 34 Howan v1 20 eed no session desc File Settings Analyse Nu Laf e ST Sp Fr Cp ex cr psd st en fullmk lt 03 8 390
32. ength measured between opposite electrodes for a practical ECT sensor 55 i LIST OF CHANGES SINCE V1 21 1 An error in version 1 21 caused negative velocities to be ignored This problem has been corrected in V1 30 2 An additional example data file has been generated to allow the velocity measurement characteristics to be checked This file veltest bcp contains 2 seconds of forward flow at 50 concentration and two seconds of reverse flow also at at 50 concentration with a net flow of zero The use of this file is described in a new section 5 4 3 The implementation of the Maxwell and Series concentration permittivity corrections has been improved in the Reconstruction Window An additional permitivity parameter Ksolid corresponding to the ratio of the bulk or solid permittivities of the two materials inside the sensor must now be entered in addition to the existing figure K which is the ratio of the permittivities of the mixture at the lower and upper permittivity calibration points More details of the use of the Reconstruction parameters window are given in section 7 3 4 A new facility has been introduced to allow the sensor Capacitance Permittivity C K characteristics to be linearised using a sensor coefficients file which contains data derived from a number of sensor calibration files for materials having a range of permittivity values The use of this lineraisation process improves both the image and concentration mea
33. ensor number of measurement electrodes in each measurement plane nth electrode segment sampling frequency frames per second anti aliasing filter frequency integer multiplier parameter to determine required minimum spacing Ls between measurement planes Effective average relative permittivity of sensor contents with sensor filled with lower permittivity material Effective average relative permittivity of sensor contents with sensor filled with higher permittivity material axial length of earthed electrode axial length of flow structure axial length of driven guard electrode axial length of measurement electrode axial separation distance between centres of sets of measurement electrodes Correlation coefficient Volumetric flow rate of lower permittivity component of 2 phase mixture Volumetric flow rate of higher permittivity component of 2 phase mixture Flow volume sampling interval 1 f seconds separation between centres of measurement planes Ls 54 At tl t2 Zl Z2 time interval between succesive frames s Time period window for correlation calculation start of flow measurement period end of flow measurement period transit time of flow structure between measurement planes also time delay in correlation equation flow velocity between measurement planes Typical capacitance per unit length measured between adjacent electrodes for a practical ECT sensor Typical capacitance per unit l
34. erating and flow algorithm parameters which are saved automatically in the Flowan ini configuration file These parameters are then read automatically into the FlowanRT program when it is started The ECT32 software is then configured to control the capacitance measurement system and then FlowanRT is configured to display and process the streamed data data in the required format Once all of the software has been configured ECT32 is set to stream live or captured capacitance data and this is displayed simultaneously in both the ECT32 and FlowanRT windows 10 2 OVERVIEW OF SOFTWARE OPERATION FlowanRT can be used with either live or experimental data It s operation will be described initially using the example data files supplied with the Flowan software FlowanRT requires the ECT32 program to be running simultaneously with FlowanRT and it is therefore necessary to adjust the PC display screen to show both the ECT32 and FlowanRT windows simultaneously 10 3 INITIALISING FLOWAN Open the Flowan software NOT FlowanRT by clicking on the Flowan icon in the ECT Software group window and load the gravityflow ini configuration file as described in section 2 4 Then close the Flowan software This will automatically save the settings in the gravityflow ini file to the Flowan ini configuration file Note that to use FlowanRT with any other data file or live data the correct sensitivity and zone maps must be loaded when Flowan is initialised 10 4 IN
35. es are selected In this case the previously selected zone maps are used 2 7 CONFIGURATION FILE STATUS FOLLOWING INSTALLATION OF A NEW VERSION OF FLOWAN When a new version of the Flowan software is installed it will over write all of the program files including the Flowan ini configuration file which contains all of the settings parameters as defined in the Settings menu which were in use with the previous version of the software As Flowan automatically loads the Flowan ini file when it starts up the functionality of the program may therefore appear to be quite different following the installation of the new software because it will have loaded different settings parameters from those in previous use To avoid this problem it is therefore important to save the current Flowan ini file to a new and unique file name eg oldconfig ini before installing or updating the Flowan software The previous configuration file oldconfig ini can then be loaded as described in section 2 4 following the installation of the new software This will allow the data in the Flowan window to appear in a similar format to that viewed with the previous version of the Flowan software If all else fails a reference configuration file refconfig ini containing basic setings which should allow almost any normal data file to be analysed is 1s now supplied with the Flowan software The values of the settings parameters in this file are given in Appendix 2 Once
36. f captured data 32 8 2 ZEROING THE CAPTURED DATA Figure 8 1 shows that there is a zero offset problem in the captured data and it is therefore worth dealing with this problem before processing the data further Select Settings gt Zero and set the menu to zero the first 6 seconds of data as shown in figure 8 2 1 below fer settings From Start Length E Set ero Close Cancel Figure 8 2 1 Zero settings window Click on the Set Zero button and then close the window The corrected Flowan window shown below will appear Select the centre zone Howan v1 20 gravityflow no session desc File Settings Analyse Help Nef Ld iL Z wif rijan Sp Fr Cplex cr psd st en ful mk lt gt BME Es 03 6 435 0 25 0 2 0 15 0 1 0 05 Normalised Concentration Speed crn Sec Ok 0 05 0 1 6 Time Sec Plane 2 Plane 1 1 Derived 0 06 0 14 0 04 0 18 0 05 08 06 0 4 0 2 0 2 0 053s 246 9 pk 0 664 fms 10 5 Elec 8 Meas 28 Frames 2631 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 2631 ave rate 200 fps Figure 8 2 2 Gravity flow data after zero correction Note that the Plane 1 concentration data green is at a higher overall level than that for the plane 2 red data This is not a measurement error but is simply a result of lowered concentration caused by the acceleration of the plastic beads under gravity betwe
37. flow User Manual 16 5 VIEWING VELOCITY DATA The principle of the method used in the Flowan to calculate velocity and flow data is described in detail in Appendix 1 which contains detailed information about the choice of parameters used to calculate the flow velocities 5 1 CALCULATING THE GOLF BALL VELOCITY The velocity of the ball can be calculated by correlating the concentration images on a zone by zone basis between the two measurement planes This is carried out as follows Click the LH mouse cursor between the two concentration peaks at a time around 5 88 seconds Select Analyse gt Velocity field The average velocity in each zone will be calculated and the velocity of the ball in the selected zone will be displayed as a blue line as shown in figure 5 1 below Howan v1 21 golfball no session desc BEE File Settings Analyse Help N j Laff zfvf rifa sp Fr cp ex cr psd st en full mk lt gt 1 500 QJ e Normalised Concentration Speed cm Sec Plane 2 Plane 1 0 01 0 00 0 00 0 00 0 8 0 6 0 4 0 2 0 2 0 054s 239 0 pk 0 963 fms 10 9 Elec 8 Meas 28 Frames 2631 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps E Figure 5 1 Zoomed Flowan screen showing velocity plot for centre zone In this case the velocity in the selected centre white zone is constant with a value around 240 cm s
38. golf ball data ball outside sensor measurement planes 14 Note that the two circular ECT images are now showing 0 concentration as the sensor is empty and also note that the correlogram is now showing no correlation peak as there are no concentration signals present other than measurement noise 4 3 ZOOMING THE DISPLAY As the only area of real interest is the time perod for which the ball is inside the sensor we can examine this time interval in more detail using the zoom controls We will use these tools to examine the measured data between the new time limits of 5 5 and 6 5 seconds as follows Left click the mouse on at a point approximately 5 5 seconds in the upper Data display window Right click the mouse and select start point Left click the mouse on at a point approximately 6 5 seconds in the upper window Right click the mouse and select end point Right click the mouse again and select the Zoom option The screen display will change to that shown in figure 4 3 1 below Hlowan v1 21 golfball no session desc irl Es File Settings Analyse Help Nu id iL Z vif Fifan sp Fr cplex Cr psa st En full mk lt gt 1 D Normalised Concentration eS E m Sj Speed cm Sec Plane 2 Plane 1 0 01 0 00 0 00 0 00 Elec 8 Meas 28 Frames 1823 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps Figure
39. he Network Connection window shown below will appear Target Network Address li 92 768 0 100 3001 Protocol TCP IP Lib Info Reduced Frame Rate Send Even fi aa Frame Connect iri No Connection Figure 10 5 4 Network connection window In the Target Network Address box enter the network address of the computer running FlowanRT followed by a colon and then the FlowanRT listening port number For example in figure 10 5 4 the network address is 192 168 0 100 and the port number is 3001 Note that PCs supplied with PTL ECT systems are all set up to have this network address 42 Click the Connect button The Network Connection window changes to show that the connection has been established as shown below Network Connection Target Network Address li 92 7168 0 100 3001 Protocol TCP IP Lib Info Reduced Frame Rate Send Ever fi Frame Finish Connection successtully created Figure 10 5 5 Network connection window following connection Click on the Finish button The display reverts to that shown in figure x ECT32 is now connected to FlowanRT The next step is to configure the FlowanRT window to display the data to be streamed from ECT32 10 6 SETTING THE FLOWANRT DISPLAY PARAMETERS 10 6 1 THE FLOWANRT WINDOW FlowanRT Replaying data from file 002 7 92 kg bcp g Oj x axis V Holdup 0 72 2000 upper limit V Ave speed 450 4 cm s V FlowRate 112
40. ical set of output data is shown in figure 9 3 Wheat_AH_m1_loose_full ocp vol 28226cm 3 mass 28226g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_AH_m2_loose_full obcp vol 28230cm 3 mass 28230g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_AOH_m1_loose_full bocp vol 28225cm 3 mass 28225g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_AOH_m2_loose_full bcp vol 28239cm 3 mass 28239g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_APW_m1_loose_full bcp vol 28219cm 3 mass 28219g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_APW_m2_loose_full bcp vol 28221cm 3 mass 28221g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_CH_m1_loose_full bcp vol 28229cm 3 mass 28229g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_CH_m2_loose_full bcp vol 28222cm 3 mass 28222g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_CH_m3_loose_full bcp vol 28233cm 3 mass 28233g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_FR_m1_loose_full bcp vol 28228cm 3 mass 28228g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_FR_m2_loose_full bcp vol 28222cm 3 mass 28222g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_FR_m3_loose_full ocp vol 28223cm 3 mass 28223g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_TR_m1_loose_full bcp vol 28252cm 3 mass 28252g Ave Vel cm sec Min 100 z1 Max 100 z1 Unacc 0 0 Wheat_TR_m2_loose_full bcp vol 28228cm 3 mass 2
41. ies present in the flow pattern then the correlogram will have two separate and valid peaks However in many practical flow regimes there will be a range of flow velocities and the velocity information will be blurred together producing multiple peaks in the correlogram Although the correlogram will in principle contain all of the information about multiple delay times and dispersion range of velocities this complicated information is difficult to extract from the correlogram in this type of flow situation Peak finding by curve fitting or simply by taking the highest peak can lead to sudden jumps in what is actually a smoothly varying situation when one peak gradually increases at the expense of another and at one point or another has a higher numerical value In this type of situation peak location using a centre of area calculation technique can produce smoother velocity profiles but in practice seems less reliable overall A1 7 CORRELATION WINDOW SIZE The condition that the correlation window must be always be larger than the transit time of the flow between the 2 measurement planes is necessary but not sufficient The correlation window must be long enough for the largest flow structures to pass from the first end of the first plane to the second end of the second plane Because of the finite lengths of the measurement electrodes this time will be longer than the nominal spacing between the centres of the measurement electrode
42. ile name Note that the file name should contain the extension txt The following points should be noted when using batch mode 37 1 If the data files are large the analysis will take a considerable time typically many minutes 2 If a constant velocity is set the Auto zero option in the batch window must not be checked 3 The results will be processed for a period of time nominally equal to that of the recording period However some data will be missrd at the start and end of the file equal to the length of the correlation window set in the correlation settings menu So if there is 10 seconds of data and the correlation window is set to 1 second only the middle 8 seconds of data will be processed 4 The batch analysis option can be used to measure the average concentration by entering a fixed velocity for the data file eg 100cm S and calculating the volumetric flow for this velocity It can then be compared with the maximum possible flow which can be calculated using the formaula Max flow A V T where A is the internal cross sectional area of the sensor in cm 2 V is the set velocity 100 cm S and T is the period of the analysed data measurement duration 2 correlation window length in seconds 5 The remaining control buttons in the batch window allow individual high lighted files to be analysed Analyse or set to be the first file to be analysed in the list displayed in the window Analyse from here A typ
43. improved correlation quality 23 6 2 USE OF CONTROL BUTTONS FOR VIEWING VELOCITY AND FLOW DATA An alternative method for initiating the Flow calculations is to use the set of flow calculation control buttons which are located on the Toolbar underneath the Analyse menu heading The functions of these buttons are as follows Vi FI All Sp Cp psd Calculates the velocity in each zone Equivalent to using the Analyse gt Velocity menu sequence Uses the velocity and concentration data to calculate the zone flow rates and overall flow Equivalent to using the Analyse gt Flow menu sequence The use of this button effectively applies the Zl VI and FI buttons in sequence and allows the flow to be analysed in one button press This button switches the Data display window to show Speed on the right hand axis within the limits specified in Settings gt Correlation No data will be displayed if Analyse gt Velocity field has not been used This button switches the Data display window to show Volumetric flowrate on the right hand axis within the limits specified in Settings gt Correlation No data will be displayed if Analyse gt Volumetric flow has not been used This button switches the Data display window to show Correlation coefficient on the right hand axis within the limits specified in Settings gt Correlation No data will be displayed if Analyse gt Velocity field has not been used This button switches the Data display windo
44. ing for any zero offset areas in the concentration calculation The effect of this can be seen by clicking on the All button when the flow data is recalculated and the new data appears as shown in figure 6 1 2 below Hlowan v1 21 golfball no session desc ir Ed File Settings Analyse Help Nu Lal L Zr VI Fl All Spf Fi Cpl Ex cr psd St En ful mk lt gt 1 a mn a Normalised Concentration oa Co in Flowrate cm Sec i Plane 2 Plane 1 Derived 0 01 0 01 0 00 0 00 0 00 0 009s 1411 5 pk 0 102 fms 1 8 reconstruction time 0 172 seconds time per plane frame 0 000 seconds Volumetric flow 65 cm 3 Mass flow 37 g Volumetric flow 63 cm 3 Mass flow 36 g a Figure 6 1 2 Corrected flow data The reported flow in the text box is now the correct value 63 cm and 36g Further information about the use of the zero correction option is given in section 7 2 Note that the flow rate plot exists for a wider time period than that for the actual physical flow This is a function of the width of the correlation window used for the calculation and illustrates the averaging which occurs in the velocity flow calculations The use of a narrow correlation window will reduce this effect and allow more rapid changes in velocity to be viewed although it will also result in poorer correlation The use of a wider correlation window will give a much slower response to velocity changes but with
45. ion settings parameters can be found in section 8 9 of the Tomoflow User Manual 5 4 USE OF THE VELOCITY TEST DATA FILE A pair of test files have been included in the Examples folder which allow the operation of the velocity calculation in Flowan to be checked The first file veltest bep contains 2 seconds of forward flow at 50 concentration and two seconds of reverse flow also at at 50 concentration with a net flow of zero The secondfile veltest ini contains the initialisation data for the velocity test file 5 4 1 LOADING THE DATA Use File gt Load and elect the veltest bcp data file which is in the c Flowan Datafiles examples folder Click the Open button to load this data file Use File gt Load config to load the veltest ini configuration file which is in the c Flowan Datafiles examples folder 5 4 2 ANALYSING THE DATA Click on the All button to analyse the test data Select the centre zone in the Flowan window which should now appear as shown in figure 5 4 1 20 Howan v1 29 synthetic_flow testfile File Settings Analyse Help No Ld L Zr if rif all sp Fr ColEs cr psd stlEn full mk lt gt U 1 2 J 4 5 b fi O M rmmaNlsed _Oncentration Pine 2 g Plane 1 Time oe uae 0g 0o 0 G 0 G eee fy J e C onic time per planetramne 0 000 seconds Volumetric flaw 0 cm 3 fwd 9901ev 990 Mass flaw 0 g Figure 5 4 1 Flowan window showing velocity testdata The tw
46. is will cause the FlowanRT software to crash You have been warned 10 11 PROCESSING REAL TIME DATA The procedure for processing live data from an ECT system is almost identical to that for recorded data The only difference is that the ECT software must be set to Capture mode rather than to Playback mode to start the streaming of data Additional information on the use of the FlowanRT software can be found in section 9 of the Tomoflow User Manual 46 APPENDIX 1 MEASUREMENT OF VELOCITY PROFILES IN ECT SYSTEMS This appendix explains how flow velocity profiles are extracted from capacitance data which has been captured using a twinplane ECT system A1 1 BASIC PRINCIPLE Concentration profiles are measured at two imaging planes which are separated by a finite distance L Equivalent pixels or zones groups of pixels in each measurement plane are then correlated between the two image planes using the correlation equation R t 1 T CWO Co t t dt 1 T 2 where R T is the correlation coefficient T is a time delay parameter C 1s the pixel or zone value in the concentration profile at plane 1 C2 is the concentration value of the equivalent zone or pixel at plane 2 t is the time seconds at which the measurements are made and and T is the integration period correlation window in seconds Figure 1 shows the correlation coefficient R plotted against against time delay t for one zone of a typical set of ECT data This graph is kn
47. itional information is located at the bottom of the Flowan window as shown in figure 3 4 normalising maps radionstuction time 0 188 seconds time pat plana frame 000 seronds Figure 3 4 Flowan Text Box More detailed information about the Flowan window is given in subsequent sections 12 4 VIEWING CONCENTRATION DATA 4 1 IDENTIFICATION OF PLOTTED CONCENTRATION DATA Following the loading of a new experimental data file the top Data display window shows the average concentration expressed as a percentage of the zone when full in the nominal range 0 100 for the selected zone shown as a white section in the zone map at each of the two measurement planes as a function of time The Green trace corresponds to the average zone concentration at Plane and the Red trace corresponds to the average zone concentration at Plane 2 4 2 BASIC WINDOW FUNCTIONALITY Left click the mouse in the upper Data display window at a time around 5 9 seconds between the red and green peaks in the concentration plots Note that the time cursor can be incremented a frame at a time using the PC cursor keys left and right arrow keys on the PC keyboard Select the centre zone in the Zone map LH circular image by left clicking on it with the mouse The Flowan window should now resemble that shown in figure 4 2 1 below and shows the passage of the golf ball through the two measurement planes of the ECT sensor approximately 5 9 seconds after the s
48. its height so that it just includes the two ECT images Then move the image window upwards so that the PC screen is similar to that shown below ECT32v2 for Win32 2 31 Jan 12 2005 14 39 26 File Mode Acquisition Calibration Permittivity Model Data Display Correlation Windows Help pid ERPS Es Be ol kd Plane 1 frame 2632 time 13 155sec Plane 2 frame 2632 time 13 155sec 1 00 Model Series Model Series K 1 60 100 K 1 60 Gain 1 00 Gain 1 00 Offset 0 00 Offset 0 00 Vol Ratio 0 50 Vol Ratio 1 18 0 0 00 System Disabled Calibrated None Frame Info 2632 13 155sec 200 0 200 0fps 7 I Autostop pce E EE Framerate Set fioo Actual 200 0 interval msec 10 Buffer length Frames 1000 Time sec 10 00 Load Saye Dawe AtoShpess gt YX OOR 42 BM O 4 A S 3 E2BG ac At 15cm Lni Col REC TRK EXT OVR English U K Start 2 a io Express fi 2 Microsoft Word _ ECT Software We ECT32v2 for Win32 Am HA LO BO 11 Figure 10 5 2 Adjusted ECT32 window Note that the ECT32 Control Panel can only be moved if it is in Idle mode Maximise the FlowanRT window by clicking on it in the Windows Task bar Now adjust the size and position of the FlowanRT window so that it can be viewed simultaneously with the ECT32 windows as shown in figure 10 5 3 4 I ox ele maj Si ECT32v2 for Win32 c Mal o olor BEE feel fle EE C x Plane 2 frame 2632 tim
49. itten as R41 The autocorrelation coefficient R t of C t is defined as follows Rui t A T 5 Ci t C t dt 3 T 2 The normalised correlation coefficient Rj2porm T 18 calculated using equattion 4 R jonorm T R 127 R11 0 R22 0 7 4 where Rj2 T is the cross correlation coefficient of of C t amp C t and R111 amp Ro2 T are the autocorrelation coefficients of C t amp C t respectively 50 A1 5 USE OF DIFFERENTIATION TO IMPROVE CORRELATION In some cases particularly for horizontal slugs of material the concentration values within the body of the slug are very uniform and correlation becomes difficult In this case it is preferable to first differentiate the measurement data with respect to time and then correlate the differentiated data Differentiation works well for sudden concentration changes between two levels without much structure otherwise as in slug flow A1 6 EFFECT OF FLOW PATTERNS ON CORRELATION The time delay T is the time by which the second plane information is delayed to calculate the correlogram It forms the x axis of correlograms and therefore has many possible values The time delay at the correlogram peak is conventionally taken to be the transit time of the flow structure This assumption is valid when the flow structure is frozen or identical at the two planes but is otherwise an approximation which is however good for most normal flows If there are two distinct velocit
50. o sets of 2 seconds of data are shown commencing at t 2 and t 6 seconds for the forward and reverse flows respectively The velocity is constant during both periods at 1000cm S during the forward flow period and 1000cm S during the reverse flow period The text box shows that the net flow is zero made up from equal and opposite f positive and negative flows of 990cm 21 6 VIEWING FLOW DATA Once the velocity profiles have been calculated for each zone it is possible to calculate the flow profiles and overall flow rate for each frame of data 6 1 FLOW RATE CALCULATION The flow calculations are carried out by multiplying the average concentration and velocity values in each zone and then multiplying this figure by the zone area which gives the instantaneous flow rate in each zone These individual zone flow rates are then summated over the pipe cross section for each frame of data to give the average flow rate per frame These average frame flow rates are then summated over all of the frames of captured data to give the overall flow It should be noted that these calculations give the volumetric flow rates and overall volumetric flow These figures can be converted into mass flow rates if the density of the material is known and entered in the Settings gt Correlations gt Density box The configuration file golfball ini contains the correct value of density 0 57 for the golf ball To calculate the flow rates select Analyse gt Flow
51. ocity plot for centre zone 8 5 EXTENDED MENU OPTIONS Data Display menu If the right hand button of the mouse is clicked inside the main data window area a further menu apears as shown in figure 8 2 6 Figure 8 2 6 Extended menu This window has already been used section 4 3 to zoom the display It also contains a number of useful plotting and export options which are described fully in section 8 3 of the Tomoflow User Manual 36 9 OPERATION IN BATCH MODE The Flowan software can be used to process one or more data files automatically in Batch Mode which is selected using the File menu The parameters used in the analysis will be those previously entered in the Settings menu Batch mode operates as follows 9 1 TO ANALYSE A SET OF CAPACITANCE DATA FILES The capacitance data files to be analysed must first be located in a single folder and the parameters to be used in the analysis must be set in the Settings menu as for operation in normal single file mode Once this has been completed the files can be analysed as follows Use the File gt Batch Analysis menu sequence to open the Batch mode window shown in figure 9 1 Batch Analysis gt Auto ero E Chose file dir UMlST_wheatAH_m a bcep length 10 0 rate 00 0fps UMIST wheat SH omlb bep length 10 0 rate 200 0fps UMIST wheat AH ome bep length 10 0 rate 00 0fps UMIST wheat A0H_m1 bcep length 10 0 rate 200 Utpes UMlST_wheat_A0H_m2 be
52. of the sensor because the diameter of the ball is less than that of the sensor Note that the concentration values are higher in the zones at the side of the tube nearest to electrodes 6 and 7 showing that the ball passed down this side of the tube Also note the correlogram statistics display which shows a very strong peak with an amplitude of 97 7 of maximum at a time delay of 0 055 seconds and a frame delay of 11 frames As the time for each image frame at 200 fps is 0 05S a figure of 0 055S corresponds to 11 frames Moreover as the spacing between the sensor planes is 13cm thevelocity can be calculated approximately as 236 4 cm S A more accurate value calculated from the correlogram peak is 237 2 cm S as shown in the correlogram Now left click the mouse in the top window well away from the time for which the ball is inside the sensor eg around 3 seconds The new Flowan screen display is shown in figure 4 2 2 below Hlowan v1 21 golfball no session desc ef x File Settings Analyse Help Nu id iL zfvf Fifan Sp Fr Cpfex Cr psd st en full mk lt 3 000 Normalised Concentration Speed crn Sec l ar Time Sec i Plane 2 Plane 1 4 Derived 0 00 0 01 0 00 0 01 0 00 0 155s 84 1 pk 0 118 fms 30 9 Elec 8 Meas 28 Frames 1823 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps Figure 4 2 2 Flowan window for
53. onitoring plastic beads falling vertically under gravity The tube and ECT sensor used to produce this data were identical to those used for the golf ball data In this section the software operation will be demonstrated using the control buttons wherever possible 8 1 LOADING THE DATA Click on the Ld button and select the gravityflow bcp data file which is in the c Flowan Datafiles examples folder Click the Open button to load this data file Use File gt Load config to load the gravityflow ini configuration file which is in the c Flowan Datafiles examples folder Select the centre zone in the Flowan window which should now appear as shown in figure 8 1 below Howan v1 20 gravityflow no session desc oy x File Settings Analyse Help Nu Ld zivij rifa sp Fr cplex cr psd st en tul mk lt gt ahes aiid M y W MN a Normalised Concentration 0 05 240 oA D Lhe AADI NEA nat WLP Phat VAN mas Oba NOLAN A HAL Nada iA DANS aa z 220 0 05 Si 0 1 200 0 2 4 6 6 10 12 Time Sec Plane 2 Plane 1 Derived 0 06 0 18 0 05 0 20 0 06 0 053s 246 7 pk 0 665 fms 10 5 Elec 8 Meas 28 Frames 2631 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 2631 ave rate 200 fps A Figure 8 1 Flowan window for gravity flow of plastic beads The window shows that the plastic beads flow for approximately 4 seconds during the 13 seconds o
54. own as a correlogram and has a peak at the time delay value t which corresponds to the distance L between the image planes divided by the flow velocity V That is at T L V which is known as the flow structure transit time Note that as the integral is a continuous function the correlogram is a continuous curve If the concentration profile images were identical in the two planes the measurement system was noise free and the correlation window was infinite the correlogram would have a normalised value of 1 at this value of time delay and zero values everywhere else However for any real system the correlogram will have a peak coefficient less than 1 depending on the degree of dispersion of the fluid flow and finite but lower values at other values of Tt as shown in figure 1 0 6 0 4 0 2 0 0 2 0 4 0 6 Figure 1 Sample correlogram 47 A1 2 PRACTICAL REALISATION The principle outlined above implies that measurements are made continuously However an ECT system captures data concentration profile images at specific time slots and at a finite frame rate per second In this case we must rewrite the integral equation 1 as a discrete summation process That 1s R p I N 5 C10 C2 n p 2 n N 2 where p is an integer frame number offset in the range N 2 lt n lt N 2 n is the measurement frame number and N is the correlation window the number of frames used to calculate the correlation factor R p at the frame off
55. p length 10 0 rate 200 0fp Analyse Analyse all Analyse from here Shop Save text Close Figure 9 1 Batch mode window in data selection mode Click on the Choose file dir button and select the folder containing the data files to be analysed The file names will appear in the data area To analyse all of the data files click on the Analyse all button The data files will be analysed and the results will appear in the data area of the window as shown in figure 9 2 Batch Analysis Iof x Auto ero E Chose file dir UMIST wheat CH_m3 bcp vol 30189cm 3 mass 301899 Ave Vellcm sec Min 10021 Max 10021 Unacc D UMIST wheat FA_m1 bcp vol 299 4cm 3 mass 299740 Ave Vellemsec Min 100 21 Max 100121 Unace 0 0 UMIST wheat FR m2 bep vol 29746cm 3 mass 297460 Ave Vel emsec Min 100 21 Max 100121 Unace 0 0 UMIST wheat FA_m3 bep vol 30372cm 3 mass 303729 Ave Vel cmsec Min 100 21 Max 100 21 Unace 0 0 UMIST wheat TR ml bep vol 28794em7S mass 287949 Ave Vellem sec Min 100 21 Max 100 21 Unaecc 0 0 UMIST wheat TR ome bep val 29053cm 3 mass 290539 Ave Vellem sec Min 100 21 Mas 1001211 Unacc 0 0 UMIST wheat TR _m3 bcp vol 29340cm 3 mass 293409 Ave Yellcmsec Min 100 21 Max 10021 Unacc 0 0 po po bo OE Oe Re Analyse f i Analyse from herel Stop Save text Close Figure 9 2 Batch mode window in results mode The results can be saved as a text file by clicking on the Save Text button and entering a suitable f
56. plane 2 and negative if the flow is from plane 2 to plane 1 If the box is unticked flow from plane 2 to plane 1 is considered positive 5 3 3 DETERMINING THE DIRECTION OF FLOW Once the flow direction convention has been set defined as described in section 5 3 2 above the actual flow direction at any point in time can be easily determined by clicking the mouse pointer in the concentration display and observing the correlogram If the correlogram peak is to the right of the central axis the velocity is positive and if it is to the left of the central axis it is negative 19 5 3 4 SETTING THE DISPLAYED SPEED LIMITS The two numbers entered in the Speed limits boxes in the correlation settings window set the lower and upper limits of the right hand velocity scale in the data display window Sensible speed limits should be set otherwise spurious velocities may be generated that have no physical meaning and the analysis process may take an un necessarily long time The correlation process will find positive and negative values of time delay and hence velocity If the direction of flow is unknown it is safest to set symmetrical positive and negative speed limits initially to ensure that the velocity plot is visible Otherwise for example if the speed scale is set to be only positive and the actual velocities are negative no velocity trace will be displayed 5 3 5 ADDITIONAL INFORMATION More detailed information about all of the correlat
57. ppears Select zone file E ES Look in O zonemaps fe o m Zonemapd_4 mat f zonemap 12_25 mat Zonemapd 9 mat Zonemap_5Sanular mat Zonemap 13 mat Zonemap_strath42 mat Zonemap _ 28 mat Zonemap_strath fe2 mat Zonemaps_ 9 mat Zonemap_strath 2 mat Zonemap1 _19 mat Figure 2 3 3 Select Zone File window The Zonemaps folder contains a number of preset zone maps for 8 and 12 electrode sensors For example zonemap8_4 is a 4 zone map for an 8 electrode sensor Select zonemap8_13 and click the Open button The 13 zone map shown in figure 2 3 4 below appears in an updated Zone and Pixel chooser window 1234567 8 9 1011121314151617181920212223242526272829303132 Mode PATE Zone E area load zone save zone Finish Figure 2 3 4 Updated Zone and Pixel chooser window Click the Finish button to accept this zone map The loaded data will appear in the upper Data Display window which will appear similar to that shown in figure 2 3 below Hwan v1 21 golfball no session desc Jaf x File Settings Analyse Help Nef Ld iL zvij rial Sp Fr Cplex cr psd st en full mk lt gt Normalised Concentration Speed crn Sec Plane 2 Plane 1 Derived 0 00 0 01 0 00 0 00 0 00 Elec 8 Meas 28 Frames 1823 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps A Figure 2 3 5 Flowan window with loaded golf ball data
58. s down a vertical plastic tube of OD 60mm and ID 53mm An 8 electrode twin plane ECT sensor with a spacing between the measurement planes of 13cm was located on the outside of the tube and a Tomoflow R100 measurement system operating at a rate of 200 frames per second fps was used to capture data over a 10 second period during which the ball was dropped down the tube The ECT sensor was calibrated using air and densely packed polypropylene beads The file name of the sample data file containing this captured data is golf ball bep 2 3 LOADING A DATA FILE Load the captured twin plane ECT data file golfball bcp using the File gt Load sequence This opens a Select file to open window as shown in figure 2 3 1 below Select file to open E Look in E Examples a f c EJ File name Jaotbal bcp Files of type bcp me Cancel Figure 2 3 1 Select file to open window Select the required file which is in the c Flowan Datafiles Examples folder The Flowan Zone and Pixel Chooser window appears as shown in figure 2 3 2 below obon ole ale ada toda dad ad ate tata aoa ooo Jetted dete de dm dw dew deo bebe bob ok kb slie Se ee ee ee ee eee 1234567 8 9 1011121314151617181920212223242526272829303132 Mode PPAM Zone Zi area load zone save zone Finish Figure 2 3 2 Zone and Pixel Chooser window Click on the load Zone map button The Select Zone map file window as shown in figure 2 3 3 below a
59. set value p In this case the correlation factor R p is a set of discrete points plotted for each value of p as shown in figure 2 0 1 0 08 0 06 0 04 0 02 0 0 02 0 04 0 06 0 06 0 1 Figure 2 Discrete correlogram from equation 1 A1 2 1 Velocity resolution enhancement by use of interpolation techniques In current ECT systems the maximum data capture rate is limited to around 200fpS ie one frame is captured every 5mS If the spacing between the measurement planes is 200 mm and the flow rate is 10m sec the transit time between the planes is 200 10000 20mS In this case only 4 frames of data will be captured as the flow moves from the first measurement plane to the second measurement plane This implies that the velocity will only be resolvable to 25 accuracy at this speed because of the severe quantisation of the measurement which results from the limited maximum frame capture rate of the measurement system However if a smooth curve is fitted to the discrete correlogram of figure 2 as shown in figure 3 the maximum value of the correlogram is seen to occur at a location between the plotted points It is therefore possible to estimate a more accurate time delay value for the correlogram peak by this means Consequently the velocity resolution of the system is increased because of the ability to interpolate between the values generated by equation 2 by fitting a smooth curve to the measured correlation values 48 Figure 3
60. sitivity map filename has been entered click on the OK button Now select the Settings gt Zone Maps menu option The Zone maps window previously shown in figure 2 3 2 and repeated here as figure 7 5 2 will be displayed Zone and Pixel chooser is lok iais ey God ad hed a ob ONON AWUN slo JoJo Jo ENE RAN JA T ete S Weed EN E EE nira ed a a mel chal ELT Ha eat debadodobababoal 1234567 8 9 1011121314151617181920212223242526272829303132 Mode PPA Zone j area load zone save zone Finish Figure 7 5 2 Zone maps window Click on the Load zone button and select the required zone map as described in section 2 3 Finally click on the Finish button The Zone map will be generated from the new sensitivity map and the user is asked to confirm that the new map is to be used in the window shown in figure 7 5 3 below Do you want to use this map Do pou want to use thie map with the current file Figure 7 5 3 Zone map confirmation window Click on the Yes button All further processing of the measured data will be carried out using the new sensitivity and zone maps The new map configuration can be made permanent by saving the configuration file 31 8 ANALYSING PARTICULATE FLOWS The golfball data gives a good insight into the operation of the Flowan software but this data is not typical of most practical flow regimes In this section we will use a set of more realistic flow data captured by m
61. sor C K charcteristics are corrected using a sensor coefficients file see 10 below 10 Pick Coeff file The sensor coefficients file to be used with option 9 above is selected using this box The sensor coefficients file can be generated using the Recal softare from the sensor capacitance permittivity file which contains data from a number of sensor calibration files for a range of dielectric materials havving differing permittivities 7 4 SETTING A CONSTANT VELOCITY FOR THE FLOW CALCULATION It is possible to set a constant velocity for the flow calculation This allows the effect of changes in the reconstruction parameters to be viewed independently of any effects these may have on the velocity and flow calculations To set a fixed velocity Load the required data and configuration files in the normal way Select the Settings gt Set fixed velocity menu option The Velocity window shown in figure 7 4 1 below will appear Figure 7 4 1 Set fixed velocity window Type in the required velocity in this case 1000 cm S and click The OK button The set velocity will be shown in the data window as a blue line Figure 7 4 2 shows a typical example 29 Howan v1 31 gravityflow no session desc File Settings Analyse Help Nu Ld cL 2c vif Fi aul sp Fr Cplex Cr psd St en full mk lt gt 2 116 1 MOMlMalsed _Loncentration 0 Plane 2 lane 1 rae Sec eee 0 56 0 48 O35 0 40 000 fy YE onc i 053s 2
62. surement accuracies and is again described in section 7 3 5 A facility to impose a constant velocity on the flow calculation has been included in section 7 4 This option allows the effect of changes in the concentration calculation to be seen more clearly 6 The method for changing sensitivity and zone maps has been improved and is described in section 7 5 Changes from v1 30 to 1 31 Problems loading new sensitivity maps have been corrected Changes from v1 31 to v 1 33 Batch processing mode modified to allow constant velocity to be set and used in batch mode Note auto zero setting in batch mode Allows calculation of overall concentration But must correct for correlation window length UG notes Extra zone map for one zone Inversion problems K inverts Derived image problems normalisation etc Display of plotting Flow is overall not zone based Reverse play of ECT32 crashes Flowan 56
63. tart of data capture Hlowan v1 21 golfball no session desc ir Es File Settings Analyse Help Nu id zivij rifau Sp Fr cplex cr psd st en tui mk lt gt 5 900 Normalised Concentration Speed cm Sec Peer Time Sec Plane 2 Plane 1 Derived 0 00 0 53 0 17 0 00 0 00 Elec 8 Meas 28 Frames 1823 ave rate 200 fps Loading Capacitance file Contents of capture mode buffer Elec 8 Meas 28 Frames 1823 ave rate 200 fps E Figure 4 2 1 Flowan window for golf ball data ball inside sensor 13 Move the time cursor one frame at a time using the PC cursor keys and note how the circular images at the two measurement planes change The concentration plots and the image sequences both show that the ball passes through measurement plane 1 first and then passes through measurement plane 2 that is plane 1 of the sensor is the upper plane The figures above the plane 1 and plane 2 concentration images give the concentration values for the selected centre zone 100 when the ball is present and for the overall sensor volume around 60 for each frame of data Adjust the time cursor location using the cursor keys until the ball image size is maximised at one of the measurement planes eg at 5 910 seconds Now select different zones with the mouse and notice how the measured concentration varies over the cross section of the sensor It is a maximum at the centre of the sensor and reduces towards the edge
64. the scroll box The available options scroll up or down as black text on a light grey background When the required option appears it is selected by left clicking inside the scroll box when its appearance changes to highlit grey text on a dark blue background This is equivalent to clicking an OK or similar button in a Windows interface to confirm the parameter selection Note that it is not sufficient to merely scroll to the required option it must be selected as described above otherwise the previously selected or default option will remain in effect 1 3 SOFTWARE INSTRUCTION CONVENTIONS The Flowan user interface window contains a combination of menus and control buttons In this Flowan User Guide we describe menu use in terms of sequences in shorthand format such as File gt Load gt filename This means Left click on the File menu in the Windows menu bar a drop down menu appears Left click on Load in the drop down menu Select the required Filename after locating the appropriate folder if necessary 1 4 THE FLOWAN CONFIGURATION IND FILE When Flowan starts up it loads a special default Configuration file Flowan ini This file contains software control parameters which are defined by the user in the Flowan Settings menu These settings parameters are automatically saved to this special file each time the Flowan program is exited As the data in this file is overwritten each time the Flowan program is run it is a good
65. w to show External data on the right hand axis within the limits specified in Settings gt Display settings No data will be displayed if external data has not been loaded through File gt Load external This button switches the Statistics display window to show correlation coefficient This button switches the Statistics display window to show power spectral density 24 7 OTHER IMPORTANT PROGRAM OPTIONS A full listing of the functionalitity of the Flowan menu options is given in the Tomoflow User Manual The use of the some of the more important menu options in the Settings menu will be discussed briefly in this section 7 1 DISPLAY PARAMETERS 7 1 1 Concentration scale The range of concentration values displayed in the upper display can be set using the Settings gt display gt concentration plot limit boxes To show the effect of changing these values select File gt display gt Concentration plot limits and input the values 0 1 and 0 1 into the limit boxes as shown in figure 7 1 1 below Image gain Image mode Correlogram zoom Concentration plot limits for fon Mass Vol decimal places as Ce Zoom position 5 555 6455 Plot Flowrate window onal Left axis grid E Right axis grid E Ext limits image limits External data limits 0 1 External data cor zone 13 Find offset External data mult offset 4 0 Ok Cancel Figure 7 1 1 Display settings sub menu Click on OK and a the screen will be upd
66. wing flow data 6 1 Flow rate calculation 6 2 Use of control buttons for viewing velocity and flow data ds Other important program options 7 1 Display parameters 7 1 1 Concentration scale 7 1 2 Gain of circular ect images 7 2 Zeroing options 7 3 The Reconstruction menu 7 4 Setting a constant Velocity for the flow calculation 7 5 Changing the sensitivity and zone maps 8 Analysing particulate flows 8 1 Loading the data 8 2 Zeroing the captured data 8 3 Viewing the concentration data 8 4 calculating the velocity and flow data 8 5 Extended menu options data display menu 9 Operation in batch mode 9 1 To analyse a set of capacitance data files 10 FlowanRT 10 1 Introduction 10 2 Overview of software operation 10 3 Initialising Flowan 10 4 Initialising FlowanRT 10 5 Initialising ECT32 10 6 Setting the flowanRT display parameters 10 6 1 The flowanRT window 10 6 2 Setting up FlowanRT 10 7 Streaming the data 10 8 Interpretation of data 10 9 Further information about the FlowanRT window 10 10 To process another data file 10 11 Processing real time data Appendix Measurement of velocity profiles in ECT systems A1l 1 Basic principle A1 2 Practical realisation A1 2 1 Velocity resolution enhancement by use of interpolation techniques A1 2 2 Effect of width of correlation window A1 3 Appodisation A1 4 Normalisation of correlation coefficients A1 5 Use of differentiation to improve correlation A1 6 Effect of flow patterns on
67. ws averages out variations in velocity whereas the use of shorter windows allows more velocity structure to be seen The optimum choice of window size depends ultimately on the application For the closest approximation to mathematical exactness high resolution concentration profiles using zones containing only a few individual pixels and captured using a sensor with short electrodes should be used A1 8 CALCULATION OF FLOW Once the velocity profile has been calculated it is necessary to take the products of the concentration and velocity profiles and integrate these across the pipe section to obtain the total flow The default flowan method is to take the average of the concentration in the same zone in each of the two measurement planes and to multiply this average value by the velocity in the same zone Alternatively the concentration in either plane can be used if there are known problems with the absolute concentration values in the other plane 52 The reference configuration file refconfi ini contains the settings in the windows below APPENDIX 2 SETTINGS DATA IN REFCONFIG INI CONFIGURATION FILE Sensor length Pipe diameter ii Density Units length mass Speed limits oot 1000 Only seek valid speeds 3 F Display settings riage gain Image mode Corelogram zoom Image display limits Wass vol decimal places Speed resolution Window Minimum correlation oom position Plot h

Flowan software User Guide - Process Tomography Limited

Contents

Download Pdf Manuals

Related Search

Related Contents