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  • What's new in PHOENICS May 2009; TR006
    object described here Only one Wind object is allowed and it always fills the entire domain Based on the wind direction it creates inflow boundaries at the domain edges using logarithmic or power law profiles on the upwind faces and fixed pressure boundaries on the downwind faces In addition the upper or sky boundary can also be made into a fixed pressure boundary Ambient Pressure and Temperature Main Menu Properties Panel The Ambient pressure and Ambient temperature entries set the pressure and temperature prevailing outside the domain These values can be used if desired to set the external pressure and temperature at all INLET WIND WIND PROFILE OUTLET FAN and PRESSURE RELIEF objects When Initialise from ambient is set ON the default the initial values of pressure P1 and temperature TEM1 are always made consistent with the ambient values set here When Set buoyancy from ambient is ON the default the reference temperature for Boussinesq buoyancy is set to the ambient temperature or for density difference buoyancy the reference density is calculated from the ambient pressure and temperature Inform Commands attached to Objects Many objects types have a button labeled InForm Commands on their attributes page This leads to a dialog from which a selection of InForm commands can be attached to the current object The usual format of an InForm command is as follows KEYWORD of VARIABLE at LOCATION is FORMULA with CONDITION KEYWORD defines what the In Form command is setting VARIABLE defines which SOLVEd or STOREd variable it is to apply to LOCATION defines where FORMULA defines what CONDITION sets the conditions under which it will happen The dialog allows such commands to be created with the LOCATION keyword being taken as the name of the current object InForm commands created in this way are held in the Q1 together with the remaining object attributes As an example the image below shows the settings required to make the inflow mass source and velocity at an INLET a linear function of the Z height Patches for User Defined Object Object type OBJ TYPE USER DEFINED OBJ PATCHES patch1 patch2 patch3 patch4 patch5 OBJ PATCHES patch6 patchn The PATCHES attribute contains a list of the patch names associated with this object As many PATCHES lines as needed to hold all the patch names can be used All settings relating to the PATCH and COVAL statements linked to a user defined object are printed in the relevant Group these can be Groups 11 12 13 or 23 The name of the controlling object is written as a guiding comment The first location argument of PATCH usually IXF is set to 1 to indicate that the patch is to be linked to an object The remaining five location arguments are zero As many PATCH commands can be attached to one user defined object as required In earlier pre 2009 versions the IXF location argument was used to hold the object number This method is still recognised on reading a Q1 but

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  • What's new in PHOENICS April 2008; TR006
    line up thus eliminating spuriously thin cells The drawing of objects in wireframe has been extended to a per object basis The master wire frame toggle operates on the selected object s reverting to all objects if none are selected When the grid mesh display was on the grid mesh dialog would appear for a mouse click anywhere on the screen It now appears only when the mouse is over the mesh In addition objects can still be selected from the screen when the grid mesh display is on by holding down the Ctrl key Changes to VR Editor Objects can be tagged to extend to the domain end They can also be tagged to always lie at the domain end This makes changing the domain size easier as tagged objects will follow automatically For the WIND PROFILE object the profile starts in the first un blocked cell in each column Previously it always started at the lower boundary of the object This makes it easier to introduce wind profiles over terrain objects as shown simply below In FLAIR the fire and smoke dialogs have been updated to use current standards terminology The Smoke Settings dialog now refers to Heat of Combustion Particulate smoke yield and Mass specific extinction coefficient These values can be found in references such as the CIBSE Guide E In FLAIR diffuser objects can be rotated about any axes Previously they had to align with the grid The InForm Editor now renamed Save Block Editor and other TCL based utilities such as Facetfix are now supplied as executables so there is no need to install TCL Changes to the Earth Solver MOFOR has been enabled in parallel PHOENICS CVD has been enabled in parallel PHOENICS To reference the value of a variable at a specific location

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  • What's new in PHOENICS August 2007; TR 006
    shape Save as a case and Open existing case save and restore intermediate step sweep files In Flair HOTBOX the file holding the fan characteristics curves can be edited directly from within the interface In Flair HOTBOX the list of fans present in the fan data file is presented as a selectable list In Flair there are two sight length variables for weakly reflective and light emitting objects Point history object can select which variable s to create time history information for Changes to the Earth Solver When PARSOL and GENTRA are active together the particles will bounce from the true facetted surface of the object Previously they bounced from the underlying fully blocked cells which could give rise to spurious reflection The calculation of forces and moments on blockages has been extended to non facetted objects those which use cube dat as a geometry file In addition more control has been added so that the user can select which objects are included or excluded from a global summation of force and moment The drag and lift coefficients can also be printed if the user supplies normalising areas The calculation of forces and moments is correct for cylindrical polar coordinates

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  • What's new in PHOENICS June 2006
    as well as for plates By setting the surface velocity a range of cases involving steady movement can be treated as steady state In Cartesian co ordinates there is a Spin option which sets the surface velocity as if the object were rotating about its axis In Polar the slide velocity can be in m s or rad s The following image shows a bar being pulled at constant speed through a Polar domain The input for multiple STL import is now taken from a multiple file selection dialog not from a list file as previously For MOFOR the MOF files controlling the motion can be created and edited directly from the Sources page of the Main menu The Editor can output the entire geometry in TECPLOT format Each object is shown in TECPLOT as a zone A TECPLOT macro is also written which sets common flags and performs common data manipulation such as calculating absolute velocity and performing Cartesian polar transformations In total 3 files are involved TECGEOM DAT containing the geometry and PHOENICS MCR the macro are written by the Editor TECDATA DAT containing the solution is written by the Earth solver The image below shows the geometry for an offshore platform approximately 120 objects exported to TECPLOT 10 Changes to the Earth Solver When PARSOL is active the cut cells are calculated properly for polar geometries For buoyancy driven flows the effect of buoyancy on turbulence can be significant In stably stratified flows such as smoke layers turbulence can be damped Conversely in the vicinity of plumes the turbulence can be enhanced These effects are implemented in the K e models via an additional source term The choice between stable or unstable stratification was previously made by setting a constant to 0 0 or 1 0 and so could never be universally correct An auto function has been introduced which switches between the stable and unstable forms depending on the local flow direction This should produce better results for cases with zones of both stable and unstable stratification The auto option is now the default for new cases set via the Editor but constant values can still be set from the Main Menu Sources panel The solution can be output in TECPLOT format An output file TECDATA DAT containing two TECPLOT zones for each PHOENICS domain is written One zone is contains data at the cell centres adjusted for PARSOL cut cells and one contains data at the cell corners The first is better for plotting vectors the second for plotting contours and iso surfaces The image below shows the geometry and solution from Library case V146 displayed in TECPLOT 10 Domain partitioning via Transfer objects The domain partitioning technique is useful for computer simulation of flow phenomena characterised by a predominant direction of flow as for example when several chemical plant vessels are connected in series as sketched below the flow being always from left to right vessel 1 vessel 2 vessel 3 upstream direction of

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  • What's new in PHOENICS 3.6.1
    graphical user interface Many improvements to FLAIR the special purpose program for HVAC and fires in buildings Extensions to the PHOENICS Commander A re working of Shapemaker which can now add and store non geometric attributes of objects as well as creating their shapes Easier remote access via PHOENICS on line The use of dynamic storage in all modules Major upgrades to PHOTON and AUTOPLOT Restoration and extension of parallel

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  • What's new in PHOENICS 3.5.1
    length If the loading is more complex so will be the In Form expressions but no matter EARTH can handle them How it was done The following four steps had to be taken Providing for the solution of the vorticity components and the storage of the dilatation which is still needed but not as a solved for variable This task was trivial for the vorticity equations are Laplace like with simple load related sources Providing a PIL variable CONVAC standing for convergence acceleration which when set TRUE in the input file activates the new algorithm This was also trivial Providing coding for the sources in the displacement equations for the solid boundary cells This required much care Ensuring that all coefficients in the displacement and velocity equations were correct in near solid boundary cells This was even more demanding because of the large number of ways in which near boundary cells can adjoin What has not yet been done The immediately to be done items include provision of a sufficient for testing and exemplification set of library examples The number is large because of the variety of fluid structure interactions which can arise in practice provision of explanatory documentation which because of the novelty it is believed of the approach is also no light task enabling users to set up stress in solids problems by way of the VR Editor enabling the VR Viewer to display the results More distant tasks none of which presents any difficulty of principle include Using PARSOL features to allow the deformations to be large enough to cut the cells and so have an influence on the flow Activating the transient terms on the displacement and vorticity equations Additionally using MOFOR features so as to simulate large displacement time dependent two way fluid structure interactions As a separate line of development extending the method to body fitted coordinate problems using the long existing and just as long neglected moving body fitting coordinate feature Go to contents 1 2 3 4 2 Data input and results display improvements 2 1 Data input by way of formulae In Form Background All CFD code vendors recognise that they cannot provide all the flow simulation features which some users will require Some therefore following CHAM s lead of 1981 most vendors now permit their users to supply their own Fortran or C language subroutines CHAM s now ten years old PLANT feature went further by enabling PHOENICS itself to write error free Fortran on the basis of formulae provided by the user The so far final stage of user empowerment has been CHAM s introduction of In Form which does all that PLANT could do without requiring any new coding at all In Form enables almost arbitrary specifications of data to be supplied to CFD or SFT simulations by way of formulae typed into the input file Q1 It was first introduced with PHOENICS version 3 4 and it has increased in power with each new release Here the two main developments in version 3 5 1 will be described a Prescribing the motion of moving objects Of the two main new developments one has already been described In Form allows the motion of an arbitrary number of objects to be described The following extracts from library case 360 illustrates the capability First the In Form MOVOB command dictates how the three position and three orientation coordinates vary with time by way of character strings TEXT MOFOR by In Form 2D motion of 2 objects Echo InForm settings for Group 7 INFORM7BEGIN Definition of the VR moving objects by In Form char vel gravt times vel 10 gravt 9 81 times tim MOVOB of SPHERE1 is POS times vel times vel 0 5 gravt t imes 2 0 0 0 0 MOVOB of SPHERE2 is POS times vel 0 0 0 0 0 The next line says Don t look for a MOF file INFORM7END SPEDAT SET MOFOR MOFFILE C NOTSET Finally the two objects SPHERE1 and SPHERE2 in their start of process positions are defined in the usual way as follows OBJ NAME SPHERE1 OBJ POSITION 0 000000E 00 0 000000E 00 0 000000E 00 OBJ SIZE 1 000000E 00 1 000000E 00 1 000000E 01 OBJ CLIPART cylinder OBJ ROTATION24 1 OBJ GRID 2 OBJ TYPE BLOCKAGE OBJ MATERIAL 1 OBJ TIME LIMITS ALWAYS ACTIVE OBJ INI PRESS 0 000000E 00 OBJ SCAL FIXF 0 000000E 00 OBJ NAME SPHERE2 OBJ POSITION 2 100000E 01 3 000000E 00 0 000000E 00 OBJ SIZE 1 000000E 00 1 000000E 00 1 000000E 01 OBJ CLIPART cylinder OBJ ROTATION24 1 OBJ GRID 2 OBJ TYPE BLOCKAGE OBJ MATERIAL 1 OBJ TIME LIMITS ALWAYS ACTIVE OBJ INI PRESS 0 000000E 00 OBJ SCAL FIXF 0 000000E 00 Graphical vector plots for case 360 are shown on for successive time instants by the following hyperlinks inst 1 inst 2 inst 3 inst 4 inst 5 inst 6 inst 7 inst 8 inst 9 inst 10 inst 11 inst 12 inst 13 inst 14 inst 15 inst 16 inst 17 inst 18 inst 19 b Ascribing arbitrary sources to objects The second major In Form development has been the provision of means of ascribing arbitrarily complex sources to VR objects Of course the VR editor permits sources of limited types to ascribed to objects However In Form permits the nature of the sources to be varied almost without limit The application of a source to a patch has been effected from the beginning of In Form by statements such as this SOURCE of VAR NAME at PATCH NAME is FORMULA where PATCH NAME is the name appearing in the PIL PATCH command which should precede the In Form statement This command marks in grid related terms the part of the domain inside which the source calculated by the formula will be applied In a similar manner In Form sets the sources in a VR type object simply replacing the PATCH name by

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  • What's new in PHOENICS 3.5
    menu A total of ten programs can be specified Any frequently used programs can be added here The list of open source files available for editing from File Open file for editing and for compiling from Compile 4 8 CHEMKIN Interface An item has been added to the Run Preprocessor menu to run the CKINTERP program which forms part of the interface between PHOENICS and CHEMKIN2 CKINTERP transforms the mechanism file ckm into the CLINK and TPLINK files required by CHEMKIN 5 VR Viewer improvements 5 1 Opening Files For Plotting The files to be plotted are selected during the VR Viewer start up sequence If another set of results is to be plotted clicking on the F6 icon or pressing the F6 function key will display the file selection dialog without changing any of the display settings Clicking on Run VR Viewer will restart the Viewer and reset all the display settings to default Transient Cases The dialog for selecting transient files has been changed The Use intermediate step files button is displayed if intermediate dumps have been selected in the VR Editor Main Menu Output Dump Settings panel When Use intermediate step files is selected the following dialog is displayed The symbol advances to the next stored time step to the last stored time step Similarly and go back to the previous and first stored time steps Clicking or pressing F7 or F8 will also load the next or previous time step files 5 2 Streamline Upgrade A left click on the Start Streamline button creates a new streamline using the current stream options A right click brings up the Stream Options dialog The options on this dialog are Stream line mode Lines Arrows or Ribbons Ribbons can show rotation in the flow but have the potential to look messy if the two lines making up the ribbon move too far apart Stream line direction Upstream Downstream Both Stream line coloured by Time along track Total time Current plotting variable When coloured by Track time or Total time the contour scale will show time unless Contours Vectors or Iso surfaces are turned on When coloured by track time each track will go from blue to red and the scale will show the times for the last track drawn When coloured by Total time the time scale will reflect the minimum maximum times for all the tracks Time zero is at the track start point Tracks drawn upstream will display negative time values When coloured by current plotting variable the variable used to colour streamlines is selected with the Select pressure temperature velocity variable buttons Stream line start From probe position Along a line Around a circle The dialogs for starting along a line and around a circle are shown When starting around a circle the centre of the circle is always the current probe position and the circle lies in the current plotting plane The line mode for each streamline is stored Changing the Coloured by mode will change the way all existing streamlines are coloured This image shows a circle of stream lines coloured by total time 5 3 Contour Upgrade It is now possible to switch between the default contour shading which uses 16 distinct colour bands and continuous shading which uses the full colour range selected in Windows The area averaged contour value is displayed under the probe value 5 4 Macro facility A typical use of the VR Viewer macro is to construct VR Viewer screen images and save them into one or more GIF files automatically For example if a transient case has been run with PHOENICS and a succession of phi files has been saved at different timesteps a macro file can be created to drive the Viewer to load the phi files one by one and save the images with the view of creating animations Saving VR Viewer Macros Macro files can be created by the following means Press the MACRO button on the Hand set This will bring up the MACRO Functions dialog Select Save as new then click OK The current view settings will be written to the selected file Pressing F4 or clicking the F4 icon will overwrite the currently selected Save as new file Press the MACRO button on the Hand set Select Append to old then click OK The current view settings will be added to the end of the selected file Pressing F5 or clicking the F5 icon will add to the currently selected Append file Individual views will be separated by a PAUSE command Hand editing a file with any text editor The macro commands can also be saved in the Q1 input file by placing them between the statements VRV USE and ENDUSE These two lines and all the macro lines must start in column 3 or more to ensure that they are treated as comments by the VR Editor Running VR Viewer Macros Macros can be run by as follows Press the MACRO button on the Hand set then Run Macro Click Ok and the selected file will be read and any macro commands in it will be executed Pressing F3 or clicking the F3 icon will run the currently selected macro file VR Viewer Macro Commands A full list of macro commands is given in TR 326 PHOTON USE Files For compatibility VR Viewer can also read a limited range of commands in the PHOTON command language This enables it to display images from PHOTON USE files 5 5 Plotting Options A right click on the Contour Vector or Iso surface buttons brings up the Plotting Options dialog Vector intervals controls the plotting of vectors When set to say 3 only every third vector will be drawn This can prevent vector plots on very fine grids from appearing like contour plots Plane limits sets a volume within which Vectors Contours and Iso surfaces are drawn The limits can be set in physical co ordinates or as cell numbers These settings are stored for each saved Slice 5 6 Opening and Saving Cases The File Open existing case and File Save as a case options have been made active for the VR Viewer It is no longer necessary to exit to the VR Editor in order to save the current case or to open another case 5 7 Printing Options It is now possible to send the screen image directly to any printer available to Windows This feature is common to VR Editor and VR Viewer 5 8 Background Colour The background colour used by the Editor and Viewer can be set from the Options menu Whatever colour is chosen will be used for saved or printed images 6 COSP Constant Optimising Software Package development COSP has been upgraded and evaluated since it was announced with the PHOENICS 3 4 release as a new goal seeking feature which enables so called inverse problems to be solved such as the search for the constants in a formula which will best fit prescribed experimental data New features added A utility RESLOOK window for viewing results during the searching process and breaking of the execution is provided RESLOOK window enables users to view the current COSP RES file to change the windows font to stop the iteration process and the latest result will be obtained to close window without breaking the process to hide the RESLOOK window The mathematical expressions which contain the constants being searched by COSP can be written by In Form in the Q1 file as well as through the ground file Long lines of In Form expressions separated by sign are accepted The correction of the current values of the searched constants in In Form expressions are made directly in EARDAT file COSP can select either PHOENICS or any other external program as its solver The COSP input file COSP INP has been upgraded in order to accommodate the new features and to make the operators names used in the file more meaningful For example new groups In Form Group and External Solver Group have been added Evaluation COSP has been evaluated through worked examples and also applied to the tobacco industry for filter design One of evaluation cases is to employ COSP for searching the correct boundary value for a convection diffusion problem for which the exact solution is available for comparison with the numerical prediction The mathematical descriptions for the convection diffusion problem are as follows dJ dx 1 Pe d dJ dx dx S where S 1 2 Pe 2x pi cos pi x pi 2 sin pi x Pe Boundary conditions x 0 J 1 exp Pe x 1 J 4 The exact solution is J 1 x x 2 exp Pe 1 x sin pi x The values for various number runs are shown in the following table where F is the objective function which is used to measure the difference between predictions and experiments and its tolerance can be specified by the user As seen the value at the boundary x 1 found by COSP is 3 99 compared with the correct value 4 at 105 run which took 107 sec NoRun F J at x 1 1 0 1458 2 00 10 0 109 2 50 50 0 019 4 24 105 0 001 3 99 The comparison between the exact solution and the calculated values for various number of runs are shown in the following table Pe J 1 J 10 J 50 J 105 J exact x 0 5 1 2 601 2 790 3 448 3 353 3 357 2 2 576 2 712 3 187 3 118 3 118 3 2 602 2 697 3 023 2 975 2 973 4 2 643 2 704 2 920 2 888 2 886 5 2 677 2 717 2 855 2 835 2 832 Documentation The COSP entry in the PHOENICS Encyclopaedia has been greatly extended Its contents cover What is COSP How COSP works COSP input files How to run COSP Worked examples COSP will be available to all maintained customers Whereas COSP has been provided with PHOENICS 3 4 only for interested users to try PHOENICS 3 5 will be released with fully attached COSP as part of the standard package available to all maintained customers 7 AC3D AC3D is a stand alone program which can be used among other things to create objects for use in the VR Editor AC3D produces VR compatible dat files Objects are constructed from any number of primitive objects spheres cylinders extruded polygons or they can be imported in a wide range of other formats including those of Shapemaker 3D Studio DXF and LightWave Additional tools supplied by CHAM allow the 3 Boolean operations in the figure illustrated using a box and a sphere add eg add a sphere to a box creating a bump on the box subtract eg subtract a sphere from a box to create a hole in the box or create the intersection of two objects the shared volume between two objects Any objects created can be used immediately within PHOENICS 8 Parallel PHOENICS developments Parallel PHOENICS has been available for several years both for multi processor machines and for clusters of single processor ones Many PHOENICS users have therefore been enabled to carry out simulations that would have been prohibitively time consuming if run in sequential mode Parallel PHOENICS makes use of domain decomposition but until now it has been possible to split the domain of study only in the z direction However many large simulations do not have a grid that is significantly larger in one direction than the others and indeed many large two dimensional problems have been formulated so as to use the x and y directions only for that is the most economical choice for sequential machines The ability to split the domain in all three directions is therefore very desirable so as to increase the efficiency of the operation and to enable a larger number of processors to be used PHOENICS 3 5 now possesses this ability The enhancement enables parallelisation to be applied to a much wider range of cases than before Note this feature is currently available only on LINUX and UNIX systems Windows based PCs will be added to the list shortly 9 Property selection treatment At the beginning in 1981 the material properties used by PHOENICS were only density viscosity and Prandtl Number and the thermal energy variable was enthalpy Varying properties could be selected by way of GRNDx settings and by choices of related constants RHO1A ENULB etc or the user could introduce his own GROUND coding When conjugate heat transfer became important and temperature was computed directly specific heat capacity was introduced Then the variable PRPS was invented together with the PROPS file for indicating where the various materials were to be found and what were their properties now including thermal expansion coefficient Treatment of radiation required absorption coefficients of transparent media and emissivity of surfaces Then IMMERSOL was invented which unified the radiative and conductive heat transfer treatments Now In Form allows the easy specification of any property varying according to any formula It was particularly the last development which showed how non uniform the internal handling of material properties had become because of its history and which therefore motivated its reorganization As a consequence of this reorganization all properties are now handled in a uniform manner in that they can be stored three dimensionally set as constants or functions printed out under relaxed and so on Although older methods of property setting are still operational it is the use of In Form s PROPERTY statement which is recommended To assist users to understand and benefit from the new treatment a properties document TR 004 has been added to the hard copy documentation 10 MFM developments The main development connected with the multi fluid model of turbulence has been the provision of means of solving for continuously varying attributes Therefore if the gases in a turbulent combustor are treated as a population of say 20 different fluids distinguished by their fuel air ratio each is now allowed to possess its own non discretised temperature density and NOX concentration This new feature of PHOENICS 3 5 is being employed both for combustor simulations and for the gravity influenced turbulence in stratified marine waters 11 SFT solid stress fluid flow Thermal analysis developments There have been two main developments in this area namely The material properties which affect the stresses in solids namely the Young s modulus the Poisson s Ratio and the coefficient of thermal expansion are now allowed to vary arbitrarily throughout the domain of study Moreover the methods of specifying these properties have been brought into line with those used for the properties of fluids as part of the reorganization mentioned in section 9 Secondly the treatment of bending moments has been improved by the introduction of an easy to solve additional equation CHAM is sponsoring PhD work on the subject at the University of Hertford 12 PARSOL improvements The PARSOL feature of PHOENICS has many merits In particular it enables flow around bodies of complex shape to be simulated without the use of body fitted co ordinate grids as was already shown in the following picture which appeared in What s New in PHOENICS 3 4 However its implementation in PHOENICS 3 4 had some limitations of which one was acknowledged and temporarily accepted while the other came to light only in the course of experience The acknowledged limitation was an insufficiently accurate representation of conjugate heat transfer i e the circumstance in which heat transfer has to be computed between the fluid and the solid and the thermal conductivity of the latter is not so great that its temperature can be taken as uniform By careful re coding coupled with painstaking testing this limitation has been completely removed as many newly created examples in the Input Library have proved The following picture shows how the symmetry of the temperature distribution has been improved for conjugate heat transfer problem The old PARSOL result is on the left the new PARSOL one is on the right The second limitation was a tendency to produce inaccurate results even for flows without heat transfer in certain circumstances especially those in which body defining facets lay very nearly in grid defining planes This limitation has also been eliminated by the adoption of a more robust algorithm for computing which facets cut which cell edges and where It would be inappropriate to explain here the details of the new algorithm but it is worth reporting that it has the further advantage of being much faster in execution than the previous one This is particularly important now that attention is being given to moving bodies which require that the facet cuts cell behaviour must be recalculated at the start of each time step 13 COFFUS related extensions COFFUS is the name of a special purpose version of PHOENICS which simulates flow heat transfer and combustion in large furnaces It was created within the framework of the EC supported MICA project and it is now the focus of attention of another such project entitled Nice Coal Several related developments are now available within PHOENICS 3 5 as described below A revised model of coal combustion full description and application of which can be found here if on line The model is an extension of COFFUS approach significantly improving its physical basis and robustness in terms of radiation coal drying char oxidation and NOX production modelling P 1 model of radiation for gas and particle laden flows Simple realistic hopefully and robust model of NOX formation accounting for thermal and fuel bound routes A model of coal gasification including pulverized and moving bed gasifications A model of fire suppression by steam water spray 14 The library search facility The PHOENICS Input File Library contains nearly three thousand cases and more are being added

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  • PHOENICS-3.4 highlights
    PHOENICS for PCs first became popular the preferred compiler was ftn77 marketed by Salford Software which used Salford s DBOS memory management system Although PC PHOENICS has been supplied in recent years with Digital now Compaq Fortran compilers some users still hanker after the speed of compilation larger fonts and general sturdiness of the earlier product PHOENICS 3 4 is therefore now been supplied in two versions Digital Compaq and Salford DBOS and it is recommended that whoever wants to enjoy the different advantages of both should order both The former has the better graphics the latter has better text but will not work with NT If PHOENICS 3 4 has already been installed on your machine click here to see the commands which activate the Salford Dbos executables 5 MIGAL solution speed up for large problems The larger the grid size the longer the computer time as all CFD users are aware and it is also known that multi grid solvers can significantly limit the increase That is why CHAM and Michel Ferry R D have collaborated to attach the latter s MIGAL multi grid solver to PHOENICS MIGAL has been demonstrated for large problems to effect very great time reductions see phoenics d polis d enc migal enc mig htm 5 For further information click here 6 Goal seeker the input optimiser PHOENICS 3 4 is being delivered with a new goal seeking feature which enables so called inverse problems to be solved such as the search for the constants in a formula which will best fit prescribed experimental data What happens is that PHOENICS performs multi runs again and again for example 1000 or more times At the end of each multi run the goal seeking part of EARTH compares the predictions with the experiments and then adjusts the constants in such a direction as will it hopes make the agreement better Because Goal Seeker is new CHAM cannot yet report extensive achievements However its potential is great so it is being provided for interested users to try 7 VR enhancements to editor and viewer The VR Editor and Viewer enhancements are far too numerous to be listed High lights are Common to VR Editor and VR Viewer Lighting enabled curved objects no longer appear flat if all facets are the same colour Improved transparency solid objects no longer disappear when moving behind transparent objects during rotation The probe can pass through cyclic boundaries The display of the Satellite Command Prompt window can be turned off It comes back automatically if a Q1 requests user input The shadow of the dialog box does not appear in saved images from File Save Window As The Unix and Salford VR Editor VR Viewer now have same Main window hand set appearance as the Windows Compaq version VR Editor BFC mesh generator accessible from Main Menu Geometry panel Also new tutorials on BFC mesh generation Gridmesh dialog updated to allow setting of time steps time regions and easy editing of

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