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  • WORKSHOP - In-Form: Time-varying Heat Source
    ambient was ON so the reference density has been set automatically from the ambient pressure and temperature The value should be the density of air at 25 C which is 101325 287 25 273 1 1847 kg m 3 Enter numerical settings Click on Numerics Set Total of number of iterations to 50 Click Previous panel Set output controls Click on Output then on Settings next to Field dumping Set the step frequency for dumping to 1 and the start letter for PHI CSG1 to a The Earth solver will write files called a1 a2 a3 and so on Click on Top menu and then on OK to exit from Menu Create Objects and specify boundary conditions Click on the Object Management button O on the toolbar or on the hand set This will display a currently empty apart from the domain list of objects Create the openings In the Object management dialog click on Object New and New Object Change name to UP Set Position and Size of the object as Xpos At end Xsize 0 0 Ypos 0 0 Ysize To end Zpos 0 0 Zsize To end Define Type Outlet Click on Attributes You will see that the External temperature is set to User set and the value is set to Ambient The external velocities are set to 0 0 Click OK to exit from the Object Dialogue Box In the Object management dialog click on Object New and New Object Change name to DOWN Set Position and Size of the object as Xpos 0 0 Xsize 0 0 Ypos 0 0 Ysize To end Zpos 0 0 Zsize To end Define Type Outlet The default attributes will be as for the UP object so do not need changing Click OK to exit from the Object Dialogue Box Create the Roof Object In the Object management dialog click on Object New and New Object Change name to ROOF Set Position and Size of the object as Xpos 0 0 Xsize To end Ypos 0 0 Ysize To end Zpos 0 0 Zsize To end Define Type Blockage In Geometry select shapes corner The new shape is not aligned correctly Click on Options then Rotation options The Rotate object face entry sets the orientation of the shape within its bounding box There are 24 possible orientations Keep changing the orientation number until you find the one which makes the shape lie correctly it is number 10 An alternative way to do the same job is to repeatedly click on the Rotate object up down buttons on the handset if it is visible Click on OK to exit the Rotation Options menu Click OK to exit from the Object Dialogue Box Create the Ground plane In the Object management dialog click on Object New and New Object Change name to GROUND Set POSITION and SIZE of object as Xpos 0 0 Xsize To end Ypos 0 0 Ysize To end Zpos 0 0 Zsize 0 0 Click on General

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_wkshp/inform/wsinf2.htm (2016-02-15)
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  • WORKSHOP - InForm Source for Object
    a new line of InForm will appear The velocity formula we want is W1 14 XG XULAST YG YVLAST In this formula XG is the distance of the cell centre in X XULAST is the domain size in X YG is the distance of the cell centre in Y and YVLAST is the domain size in Y The result is to make the inlet velocity linear in both X and Y Click on the empty button under Keyword A list of options will appear From the list select SOURCE Now click on the empty box under Var A list of currently SOLVEd and STOREd variables will appear Select W1 from the list and click OK Now to introduce the formula for W1 Click the empty box under Formula An editing window will appear Place the cursor at the top left of the input window and type in 14 XG XULAST YG YVLAST then click File and Save Exit The new formula will appear on the button When we replace the inlet velocity we also need to replace the mass source otherwise we may get inconsistencies in the pressure field Mass sources are introduced as sources of the pressure variable P1 Click Add Inform again to create a second line of InForm On the second line select Source for the Keyword and P1 for the Var iable The formula for mass flow is density times velocity Click on Formula for P1 and in the editing window type in DEN1 14 XG XULAST YG YVLAST DEN1 is the name of the density store The default source for an object is a total source for the whole object We have specified the mass flow as density velocity which is in kg m 2 s To tell Inform that the source is per unit

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_wkshp/inform/wsinf3.htm (2016-02-15)
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  • WORKSHOP - Average Values and Tabular Output by InForm
    area averaged Z directed velocity W1 This is given by Wave S W1 Ahigh S Ahigh where Ahigh is the Z directed cell face area Firstly we create an object at the location where we want to do the summations Click Settings New New object Set the Size to Xsize To end Ysize To end Zsize 0 0 Set the position to Xpos 0 0 Ypos 0 0 Zpos 15 0 Click Options and clear the tick from Object affects grid We do not want to change the existing grid distribution Click General and set the object type to User defined Change the name to AVEW1 Click Attributes to open the Object settings dialog for this object and then click Edit InForm 13 This will open the Inform Save Block Editor which is used to insert or modify InForm commands In between the save13begin and save13end lines type the following save13begin make totar is 0 0 make w1tot is 0 0 store1 of totar at avew1 is sum ahigh store1 of w1tot at avew1 is sum w1 ahigh print of w1bar is w1tot totar table in monplt csv is get w1tot totar w1 1 1 15 with head wbar w1 1 sweep save13end The meaning of these lines is as follows make totar create a single variable which will hold the total area and initialise to zero make w1tot create a single variable which will hold the velocity times area sum and initialise to zero store1 of totar sum the high area over the extent of object avew1 store1 of w1tot sum the product of W1 velocity and high area over the extent of avew1 print of w1bar print the average velocity into the INFOROUT file table in monplt csv is create a file called monplt csv containing three columns

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_wkshp/inform/wsinf4.htm (2016-02-15)
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  • WORKSHOP - Boundary Conditions and Sources
    be by the name TEMP Note 2 VR Editor Mode A heat source can be attached to an existing feature the wall by the following sequence Click on the Object management button on the hand set This will bring up the Object managemnet dialog box Select the objecty name NORTH north wall and double clik on it This will bring up the Object specification dialog box Click on Attributes then on Surface Enthalpy next to Energy source From the list of heat sources select Surface Heat Flux and click on OK Enter 5 0 in the Value data entry box Click on Total Heat Flux to toggle to per unit area Click on OK to close the Attributes dialog box Click on OK to exist from the object specification dialog box Command Mode The flux of enthalpy would be set by a PATCH COVAL combination such as Group 13 PATCH HOTNORTH NORTH 1 1 NY NY 1 NZ 1 LSTEP COVAL HOTNORTH TEMP FIXFLU 5 0 Note 3 The total source of enthalpy TEMP for the wall is the product of the flux per unit area times the wall area The first is 5 0 and the second is 2 0 x 1 the product is therefore 10 0 Note 4 VR Editor Mode A constant temperature can be attached to an existing feature the wall by the following sequence Click on the Object management button on the hand set This will bring up the Object managemnet dialog box Select the objecty name NORTH north wall and double clik on it This will bring up the Object specification dialog box Click on Attributes then on Surface Heat Flux next to Energy source From the list of heat sources select Linear Heat Source Enter 1 0E10 in the Coefficient data entry box Command Mode The values of enthalpy in the near wall cells would be fixed by a PATCH COVAL combination such as Group 13 PATCH FIXED NORTH 1 1 NY NY 1 NZ 1 LSTEP COVAL FIXED TEMP FIXVAL 5 0 Note 5 The source for a PATCH COVAL pair is S C V f With a large coefficient the effect of the source is to fix the value V f allowing for rounding errors In such a case S 0 Earth is programmed not to print the source whenever 1E10 or more appears as the coefficient to avoid rounding error FIXVAL is a huge number 1E20 If you use a smaller large number say 1E6 for the coefficient the value will still be fixed but not so closely that the resulting source is lost in rounding error Note 6 The original case 240 treats the north boundary as a wall the surface enthalpy is fixed to 0 but the enthalpy in the near wall cell is calculated The heat flux is calculated from the local enthalpy differences In the second example the heat flux in each cell is set to 5 and the local enthalpy calculated accordingly In the

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_wkshp/wsbousor.htm (2016-02-15)
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  • WORKSHOP - How to build a New Object from an existing Object
    make a copy of cube dat at the end of the list of shapes Right click on the copy of cube dat and rename it to geomtest dat Edit the copied file Right click on geomtest dat and on Open with Select Notepad from the list of applications In Notepad In the data file GEOMTEST DAT the first line gives the number of vertices making up the geometric shape Lines 2 to 9 are the actual vertices of the cube given as xvalue yvalue zvalue Line 10 gives the number of facets needed to make up the geometric figure The remaining lines define the facets The last number in these lines is the colour of the face The first four numbers of these lines are found by looking at a particular face and listing the points ANTI CLOCKWISE when the face is viewed from outside the cube In this example the original cube is There are always four numbers needed to define a facet If it is a triangular facet then one of the numbers is repeated To make a pyramid from the above change the number of facets from 6 to 5 and delete the penultimate line of the data file Change all x and y values to 0 5 when z 1 0 There will be four such lines be careful to use the same format and number of decimal places as the original numbers To change the colour of the cube to shades of red set the colour code at the end of each of the last five lines to 176 178 176 178 179 respectively Note that this value is in I3 format so you will have to remove one of the spaces before the existing 2 digit colour numbers The modified file should look like

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_wkshp/wsnewobj.htm (2016-02-15)
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  • AC3D User Guide
    ac3d Within the installation directorythere is a sub directory called Plugins extensions to AC3D can be placed in here and the CHAM plugins called chamdat p healong p and gtsbool p should be in the plugins directory normal installation of PHOENICS will ensure this is so The CHAM plugins enable the PHOENICS dat file format to be read and written directly by AC3D holes in objects to be healed and

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_info/ac3d/ac3dguid/index.htm (2016-02-15)
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  • pq1t2_1.htm
    zwlast All these actions will result in the following It is now necessary to introduce similar changes in all objects sizes and positions that depend on the domain sizes Because this is a rather laborious and tedious work we have done it for you All you will need is to copy the data file named gp25 1 from the folder phoenics d polis d tuts pq1ts pq1t2 1 into your present working directory and do not forget to introduce the corresponding changes into the incl command of the Q1 file Now run the Q1 file from your working directory in exactly the same way as you have done before When the simulation is finished open the result file in the Commander editor and compare it with the previous ones all of them should be identical Exploring the parametrization advantages If you now examine the data file for this case gp25 1 more carefully by opening it in the Commander editor window you will certainly find out that the sizes and positions of all objects which make up the scene of the labyrinth case do depend on the calculation domain sizes xulast yvlast and zwlast these being the largest values of its X Y and Z co ordinates This was not evident when these positions and sizes were expressed numerically rather than via parameters It would convenient and reasonable to have all the objects depend on the calculation domain so that any changes introduced to the domain will result in corresponding changes of the whole scene and we are about to find out how to achieve this Let us first check the effect of yvlast i e the domain Y size on the flow which being 2 dimensional should be unaffected by the change Open the data file gp25 1 in the editor window if it is not still opened clicking on File Open gp25 1 The default value of yvlast is 1 m Type 2 instead meaning that we double the domain size in the Y direction Save the file and run the case by clicking on the S E icon on the left Having made the simulation click on the END button to return to the Commander editor window Scroll to the bottom of the RESULT file where solved variables at the monitor point are plotted as a function of the iteration number You will see that they are identical to these of the previous run apart from the values of temperature The results for temperature are as shown below Variable 6 TEM1 Minval 2 011E 01 Maxval 2 140E 01 Cellav 2 021E 01 i e half the previous values The reason for this is that we did not change the heat source in the L BLOCK object Doubling YVLAST doubled the area of the inlet and so caused twice as much air to enter the temperature rise was therefore halved To rectify this we need to double the heat flux i e in the editor to change the line OBJ HEAT FLUX 0 000000E 00 1 000000E 02 in the file gp25 1 to OBJ HEAT FLUX 0 000000E 00 1 000000E 02 yvlast When you run the Satellite and solver again you should find that the earlier temperature distribution has been recovered It is also possible to prove the two dimensionality of the flow in the viewer Click the Run modules button in the tool bar and then the VRV button on the left Click OK in the File names window and you will see the simulation results of this run loaded in the viewer Click on the Contour toggle button in the tool bar to open the picture like this one Now move probe in Y direction paying attention to the probe value of pressure for this screen It will remain the same You can perform the same test for other variables for example velocity or temperature or choose another position for the probe The result of your actions will be similar the flow is truly two dimensional Let us now quit the viewer by clicking on the top right cross and return to the editor to test the effect of the other domain sizes First go to the View or edit files window and click on the q1 icon on the left We shall find the familiar q1 file in the editor window However it is not q1 that we really want to edit but the data file gp25 1 Open the gp25 1 file clicking on File Open and selecting this very file from the Open window Increase the X size of the domain by a factor of two by changing the line xulast 2 to xulast 4 Save this change by clicking on File Save File Then run the case When the run is accomplished click on the End button to see the RESULT file in the editor window Your results should be as follows Variable 1 P1 2 U1 3 W1 4 KE 5 EP Minval 1 000E 10 1 000E 10 2 704E 02 5 652E 06 4 734E 08 Maxval 1 395E 02 1 949E 02 1 000E 10 1 087E 05 2 689E 07 Cellav 1 125E 02 1 773E 02 2 253E 02 1 053E 05 2 533E 07 Variable 6 TEM1 Minval 2 001E 01 Maxval 2 320E 01 Cellav 2 017E 01 1 00 6 4 4 4 5 5 5 5 5 5 5 5 5 5 5 5 5 2 5 5 5 5 5 2 2 2 2 2 2 2 2 2 2 1 0 90 1 1 5 1 1 1 0 80 4 1 1 1 1 1 1 0 70 1 1 0 60 0 50 0 40 0 30 3 3 3 3 0 20 3 3 3 3 0 10 3 3 3 3 3 3 3 0 00 5 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_tuts/pq1ts/pq1t2_1/pq1t2_1.htm (2016-02-15)
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  • pq1t2_2.htm
    your present 3 D image to a 2 D one To achieve this go to Settings and select the Depth Effect command In the Depth Effect window either type a greater value in the box and then click anywhere on the screen or move the slider to the right thus increasing the distance between the observer s eyes and the labyrinth objects You will then see a picture like this one The IN PLATE being of zero thickness has disappeared and now only the IN BLOCK and the grid are visible The grid is uniformly distributed in the x direction but not quite so in the z direction as is confirmed by inspecting what is printed by the Satellite in the file q1ear and later by EARTH in RESULT namely Group 3 X Direction Grid Spacing CARTES T NX 20 XULAST 2 000000E 00 XFRAC 1 5 000000E 02 XFRAC 2 1 000000E 01 XFRAC 3 1 500000E 01 XFRAC 4 2 000000E 01 XFRAC 5 2 500000E 01 XFRAC 6 3 000000E 01 XFRAC 7 3 500000E 01 XFRAC 8 4 000000E 01 XFRAC 9 4 500000E 01 XFRAC 10 5 000000E 01 XFRAC 11 5 500000E 01 XFRAC 12 6 000000E 01 XFRAC 13 6 500000E 01 XFRAC 14 7 000000E 01 XFRAC 15 7 500000E 01 XFRAC 16 8 000000E 01 XFRAC 17 8 500000E 01 XFRAC 18 9 000000E 01 XFRAC 19 9 500000E 01 XFRAC 20 1 000000E 00 Group 5 Z Direction Grid Spacing PARAB F NZ 15 ZWLAST 1 000000E 00 ZFRAC 1 5 000000E 02 ZFRAC 2 1 125000E 01 ZFRAC 3 1 750000E 01 ZFRAC 4 2 375000E 01 ZFRAC 5 3 000000E 01 ZFRAC 6 3 666667E 01 ZFRAC 7 4 333333E 01 ZFRAC 8 5 000000E 01 ZFRAC 9 5 666667E 01 ZFRAC 10 6 333333E 01 ZFRAC 11 7 000000E 01 ZFRAC 12 7 833333E 01 ZFRAC 13 8 666667E 01 ZFRAC 14 9 500000E 01 ZFRAC 15 1 000000E 00 The uniformity in the x direction is a consequence of the fact that all the x direction positions and sizes of the objects happen to be multiples of 0 05 m therefore all the xfrac values are such multiples also But this accidental congruence did not occur with respect to the z direction settings If you desire to know what the grid would have been like had it not been adjusted to fit the objects paste the line obj grid no beneath each object related block of settings in file gp25 3 then run the VR Editor The grid will then appear as follows wherein the red lines have disappeared and the non fitting of the IN BLOCK and L BLOCK objects is obvious Warning If you intend to follow instructions of this tutorial you will be constantly switching between the PHOENICS Commander and the VR Editor In this case you should beware of either clicking on File and Quit to exit the VR Editor without saving all the changes made or clearing the boxes in the Save Current Settings window each time when you close the VR Editor clicking on the top right cross Only then will you preserve your Q1 unchanged the incl gp25 3 statement will be retained and you be able to make changes when necessary by editing the data file gp25 3 The grid region concept Careful comparison of the above two grids reveals that the second lacks what the first exhibits namely several red grid lines and it may be noted that some at least of these red lines do coincide in part with boundaries of objects Indeed if it is recognised that the INLET OUTLET and IN PLATE objects are not visible in this view it may be concluded that all of the red lines do coincide with object boundaries In order to confirm this remove or deactivate the grid no lines from gp25 3 re run the VR Editor then click first on the Mesh toggle button and then on the Geometry cells toggle button The image which you will see is as follows This shows all the cells which are within objects of volumetric type or adjacent to objects of cell face type and the red lines do run along the boundaries of each such group of cells Thus is revealed how the PHOENICS Satellite fits its grid to the objects it divides each of the x y and z dimensions into a sufficient number of so called regions to enable their boundaries to fit the objects and then distributes the remaining grid lines as evenly as possible between them In the present case there are four regions in the x direction and six in the z direction facts which are confirmed by the following lines in the gp25 3 file GRID RSET X 1 5 1 000000E 00 GRID RSET X 2 5 1 000000E 00 GRID RSET X 3 4 1 000000E 00 GRID RSET X 4 6 1 000000E 00 GRID RSET Y 1 1 1 000000E 00 GRID RSET Z 1 1 1 000000E 00 GRID RSET Z 2 4 1 000000E 00 GRID RSET Z 3 3 1 000000E 00 GRID RSET Z 4 3 1 000000E 00 GRID RSET Z 5 3 1 000000E 00 GRID RSET Z 6 1 1 000000E 00 Here the first four lines correspond to the four x direction regions which have 5 5 4 and 6 intervals cells respectively in each making a total of 20 the fifth line corresponds to the one region of the y direction with only one interval in it and the remaining six lines correspond to the six z direction regions having respectively 1 4 3 3 3 and 1 intervals in them making a total of 15 The above lines being shifted two spaces to the right of the first column are not active in the Q1 file but they have been inserted by the Satellite when working in VR Editor mode as a record of what it has done by way of distributing the grid lines It is its candour in doing so which allows us to take command Changing the grid distribution The following steps should now be taken so as to convince ourselves that we are indeed in command Activate the above mentioned lines by deleting the first two spaces Then re run Satellite and compare the new q1ear with the previous one They should be identical The same will be found in respect of the RESULT file if the EARTH solver is also run Let us now edit the relevant lines in gp25 3 so that they are GRID RSET X 1 10 1 000000E 00 GRID RSET X 2 10 1 000000E 00 GRID RSET X 3 8 1 000000E 00 GRID RSET X 4 12 1 000000E 00 GRID RSET Y 1 1 1 000000E 00 GRID RSET Z 1 2 1 000000E 00 GRID RSET Z 2 8 1 000000E 00 GRID RSET Z 3 6 1 000000E 00 GRID RSET Z 4 6 1 000000E 00 GRID RSET Z 5 6 1 000000E 00 GRID RSET Z 6 2 1 000000E 00 which implies that we have doubled the number of cells in each x direction and z direction region When we re run the VR Editor the grid will appear thus The pressure contours and velocity vectors when the Earth solver has been run will appear in the Viewer thus Let us see how this mere increase in the cell number has changed the non dimensional pressure and temperature Whether these complexes have been changed to approach our expectations expressed in the previous part of the tutorial The non dimensional pressure now looks like in this picture Judging by the scale we could think that the results are now even less understandable than for the previous run as the minimum value is now approaching 7 However the region where the non dimensional pressure is negative i e in the above IN BLOCK space has become smaller As to the outlet area it is practically zero As to the non dimensional temperature it is as in the following picture It is practically zero in the major space of the labyrinth increasing with approach to the heat source L BLOCK and behind the IN BLOCK as in the previous run In general the non dimensional temperature is becoming more uniform as the heat input from the L BLOCK is rather small and the air inlet velocity is small too Evidently the grid has been refined as is reflected in the result file thus even though the command describing the grid in q1 namely Groups 3 4 5 Grid Information Overall number of cells RSET M NX NY NZ tolerance RSET M 20 1 15 remained unchanged Within each region the grid distribution is evidently uniform Thus is a consequence of the fact that the last argument of each GRID line is 1 0 Let those of the four x direction regions be altered thus GRID RSET X 1 10 0 5 power law starting from low x GRID RSET X 2 10 0 5 power law starting from high x GRID RSET X 3 8 2 0 symmetrical power law GRID RSET X 4 12 2 0 g symmetrical geometric progression Displayed in the VR Editor with the Mesh and Wireframe toggles pressed the grid now appears as about which the following remarks can be made None of the non dimensional variables are displayed within the solids This is understandable for pressure and velocity but about temperature further remarks will be made below A full description of the significance of the GRID RSET command can be found in the document TR 326 here In the first x region starting from the left the 0 5 exponent clusters the grid cells towards the right thus enabling the boundary layer on the plate to be better simulated In the second region the minus sign in front of 0 5 causes the clustering to be at the lower x region rather than the higher In the third region clustering at both left and right is achieved by changing the exponent to 2 0 and placing a minus in front of the number of intervals argument 8 In the fourth region the presence of the optional g argument indicates that the geometric progression rather than power law furmula is to be used Further information can be found in the Encyclopaedia entry GRDPWR The pressure distribution and contours which result when the solver is run with this grid is shown here As to the non dimensional pressure it will be like this one Although the minimum non dimensional pressure has been reduced a little bit more as compared with the previous run the area of negative non dimensional pressure has been also reduced and in the space between the IN BLOCK and the OUTLET section this parameter is stably positive We can attribute the increase of the absolute value of the minimum pressure to the round off error The non dimensional temperature looks like in the picture which follows It is uniform enough except for the areas behind the WALL W and the IN BLOCK where its maximum values are found but these can be also explained by flow stagnation in these zones Parameterizing the grid distribution Knowing now that we are indeed in control of the grid distribution we can see how to proceed with parameterization The part of the file gp25 3 which sets the grid should be changed to the following in which three parameters are declared and set for each grid region the number of grid intervals n the power law exponent or geometric progression factor p and the character variable which chooses between power law or progression g you can find more about character variables clicking here here Declaring grid parameters integer nx1 nx2 nx3 nx4 nz1 nz2 nz3 nz4 nz5 nz6 real px1 px2 px3 px4 pz1 pz2 pz3 pz4 pz5 pz6 char gx1 gx2 gx3 gx4 gz1 gz2 gz3 gz4 gz5 gz6 Setting grid parameters nx1 10 nx2 10 nx3 8 nx4 12 nz1 2 nz2 8 nz3 6 nz4 6 nz5 6 nz6 2 px1 0 5 px2 0 5 px3 2 0 px4 2 0 pz1 1 0 pz2 1 0 pz3 1 0 pz4 1 0 pz5 1 0 pz6 1 0 gx1 f gx2 f gx3 f gx4 t gz1 f gz2 f gz3 f gz4 f gz5 f gz6 f Reading grid parameters GRID RSET X 1 nx1 px1 gx1 GRID RSET X 2 nx2 px2 gx2 GRID RSET X 3 nx3 px3 gx3 GRID RSET X 4 nx4 px4 gx4 GRID RSET Y 1 1 1 0 f GRID RSET Z 1 nz1 pz1 gz1 GRID RSET Z 2 nz2 pz2 gz2 GRID RSET Z 3 nz3 pz3 gz3 GRID RSET Z 4 nz4 pz4 gz4 GRID RSET Z 5 nz5 pz5 gz5 GRID RSET Z 6 nz6 pz6 gz6 If this is done and a further run made the results will be precisely as before if indeed your last run did have the grid settings implied above The influences of these parameters can now be explored one by one For example it may be interesting to see what is the effect of switching between the power law and geometric progression options or to experiment with the minus sign placed before that number of intervals or the p attribute More important however is to discover how many intervals are needed for the numerical solution to be accurate That is the subject of section 4 of this tutorial in preparation for which you should introduce the following few extra lines just above the reading grid parameters section Further declarations integer nx0 nz0 Further settings nx0 1 nz0 nx0 nx1 nx1 nx0 nx2 nx2 nx0 nx3 nx3 nx0 nx4 nx4 nx0 nz1 nz1 nz0 nz2 nz2 nz0 nz3 nz3 nz0 nz4 nz4 nz0 nz5 nz5 nz0 nz6 nz6 nz0 By introducing the two additional parameters nx0 and nz0 making the first equal the second and linking the other nx s and nz s to them we have thus made it possible quickly to change the fineness of the whole grid without losing the ability subsequently to make further refinements in individual regions of the grid 3 Parameters read from file Before proceeeding further it is appropriate to consolidate what has been done so far which has involved introducing parameters setting their values introducing relationships between them and observing their effects on the flow calculations The nature and rationale of these actions will become clearer if some of the entries made in the file gp25 3 are tranfserred to another file which we shall call params This will be related to q1 and gp25 3 as indicated in the following sketch You should therefore now paste into your Q1 the last three lines of the following so that it contains Groups 3 4 5 Grid Information Overall number of cells RSET M NX NY NZ tolerance RSET M 20 1 15 save3begin incl params save3end The params file is being included at this point so that what it contains about the grid wil not be over written as it otherwise would be by the RSET command which follows Now create the params file itself by pasting in the following lines most of which have appeared before in the gp25 3 file params file for library case 621 used in parameterised q1 tutorial number 2 TEXT parameterized 621 PIL parameter settings xulast 2 yvlast 1 zwlast 1 non PIL parameter declarations object parameters real invel inmass object existence parameter boolean inpxst inbxst wwxst ewxst parameters used in non dimensional variables real intem pext inarea heatflux grid related parameters integer nx1 nx2 nx3 nx4 ny1 nz1 nz2 nz3 nz4 nz5 nz6 real px1 px2 px3 px4 py1 pz1 pz2 pz3 pz4 pz5 pz6 char gx1 gx2 gx3 gx4 gy1 gz1 gz2 gz3 gz4 gz5 gz6 Further declarations integer nx0 nz0 non PIL parameter settings object existence parameters inpxst t inbxst t wwxst t ewxst t non dimensional variables intem 20 0 pext 0 0 heatflux 100 invel 0 05 inarea yvlast 0 45 zwlast inmass inarea rho1 invel Grid related parameters nx1 10 nx2 10 nx3 8 nx4 12 ny1 1 nz1 2 nz2 8 nz3 6 nz4 6 nz5 6 nz6 2 px1 0 5 px2 0 5 px3 2 0 px4 2 0 py1 1 0 pz1 1 0 pz2 1 0 pz3 1 0 pz4 1 0 pz5 1 0 pz6 1 0 gx1 gx2 gx3 gx4 g gy1 gz1 gz2 gz3 gz4 gz5 gz6 Further settings nx0 1 nz0 nx0 nx1 nx1 nx0 nx2 nx2 nx0 nx3 nx3 nx0 nx4 nx4 nx0 nz1 nz1 nz0 nz2 nz2 nz0 nz3 nz3 nz0 nz4 nz4 nz0 nz5 nz5 nz0 nz6 nz6 nz0 Those lines which have not been seen before are printed in red They provide for the possibility of removing from the scenario four of the objects IN PLATE IN BLOCK WALL W and WALL E Finally we suggest that you edit the existing data file gp25 3 and save it as for example gp25 4 by cutting and pasting your gp25 3 in the following way GVIEW P 0 000000E 00 1 000000E 00 0 000000E 00 GVIEW UP 0 000000E 00 0 000000E 00 1 000000E 00 store vabs stored var nd v is vabs invel stored var nd p is p1 pext 5 rho1 invel 2 stored var nd t is tem1 intem cp1 inmass heatflux mesg variables stored stored DOM SIZE 2 000000E 00 1 000000E 00 1 000000E 00 DOM SIZE xulast yvlast zwlast DOM MONIT 7 500000E 01 5 000000E 01 4 666670E 01 DOM MONIT 75 zwlast 5 zwlast 466667 zwlast DOM SCALE 1 000000E 00 1 000000E 00 1 000000E 00 DOM SNAPSIZE 1 000000E 02 Reading grid parameters

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_tuts/pq1ts/pq1t2_2/pq1t2_2.htm (2016-02-15)
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