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    ASCII STL files were supported however from PHOENICS version 3 6 binary STL files are also allowed There exists a directory within the PHOENICS package which contains a set of ASCII STL files of which the names can be seen by clicking here One of these has been copied into a htm file and provided with the necessary HTM tags in order that its contents can be inspected and the easy readability of its format perceived by clicking here How to import such files is discussed in detail in the report TR 326 3 STL files created by PHOENICS PHOENICS can not only use files created by other software packages it can create them itself This facility has been provided in order that the shape and quality of the body actually simulated by the PARSOL feature of PHOENICS can be inspected and the STL file produced by a CAD package may be replaced by one with fewer too far from equilateral triangles than the original possessed and therefore easier to use as the basis of grid generation The first of these is the more important for PHOENICS users and its value may be seen from the following sequence of images concerned with the use of PARSOL to secure an adequate representation of flow through an array of louvres Click here to see a disappointingly unrealistic flow pattern achieved with a grid of 46 75 Click here to see the explanation the first attempt at parsolization has made a very poor grey representation of the body green defined by the original STL file because the grid was too coarse It was activation of the MAKSTL feature of PHOENICS which showed this The grid was therefore refined appreciably namely to 120 135 this resulted in the flow seen by clicking here where

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_enc/stl.htm (2016-02-15)
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  • Scrutiny of Cut-Cell Detection
    file called PBC TEST and put the message in the file EARTH will be terminated if multi cut exists after all object detections and how the cell is multi cut by objects will be printed out in the RESULT file Option 4 Restart or Non Restart PARSOL with users treatment to illegal cells User needs to create the file PBC TEST with his her instructions in it and run EARTH with or without RESTRT PRPS The instructions in file PBC TEST are to tell EARTH which cell should be blocked by which object or which cell should be open to domain material and are used to surpass PARSOL detection The line of instruction is like IX IY IZ IDMN OBJNAME LIMBNAME in format 4I8 1X A12 A48 More details can be seen in the section of examples 3 Examples Two examples below are about to demonstrate how these functions work a small building a car park 3 1 A Small Building The building is formed by three objects roof wall and floor The coarse grid is used click here for image Take default actions by running EARTH through and DEBUG is TRUE The following message was printed out in RESULT file idmn 1 cell ix 4 iy 3 iz 1 is cut by object WALL first and then cut by object FLOOR the cell is repaired by filling domain material It can be clearly understood the cell 1 4 3 is multi cut by both wall and floor EARTH took the default action filling it with domain material because none of the objects cover the center of the cell As result the fluid flow went through the wall which was not as user wants it to be click here for image Take option 2 creating the file PBC TEST and put the message STOP IF MULTI CUT in it EARTH was terminated with popping up a message window as below click here for image The message in result file was idmn 1 cell ix 4 iy 3 iz 1 is cut by object WALL first and then cut by object FLOOR EARTH terminated due to multi cut after all object detection Then to repair the case following line was put in the file PBC TEST 4 3 1 1 floor none It means the cell 4 3 1 in domain 1 will be blocked by object FLOOR none is in the place of limb name since there is no limb name in this example Of course the cell must be within the box of the object in order to have correct INIVAL and source attached to the object The result can be seen below after repairing click here for image 3 2 A Car Park This example is simplified from a real car park case which has many multi cut cells due to the fact the thin spiral shape floor touches the cylindrical wall reasonable fine grid was used to resolve the thin spiral floor See picture below click here

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_enc/scrutiny.htm (2016-02-15)
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  • Genmix
    implications of the various hypotheses with experimental data on jets wakes and boundary layers it embodied what was probably the first ever self adaptive computational grid which enlarged or contracted to cover only the regions of interest whence its nickname the Bikini method it incorporated chemical reaction as an option click here for a lecture which mentions its role in the application of CFD to combustion it can be regarded

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_enc/genmix.htm (2016-02-15)
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  • A fourteen-fluid model applied to the steady Bunsen burner
    of the whole population are fluids 17 fuel rich unburned and 1 pure air The fluids of other kinds come into being as a result of coupling ie contact and intermingling and splitting ie production of progeny having intermediate grid locations For example fluid 5 can mix with fluid 19 so as to produce fluids 9 10 14 and 15 in proportions which the modeller is free to decide on the basis of considerations which it would be distracting to discuss here A small stream of fluid 16 stoichiometric combustion products is supplied at the edge of the burner tube to act as a lame holder d The Bunsen burner model Fig 7 also copied from 40 illustrates the subject of the study and how its behaviour simulated by the use of PHOENICS Especially noteworthy is the fact that the parabolic option is used This is of great convenience for it enabled the computations to be completed in about 5 minutes on a Pentium PC Fig 7 Diagrammatic representation of the Bunsen burner flame flame PHOENICS is used to solve the differential equations for 14 air at fluid concentrations as well as rest for two velocities and pressure entrained into The parabolic ie marching flame integration mode is used The Prandtl mixing length model is used for the hydrodynamics and to supply local coupling and splitting burner ignition rates fuel rich source gas jet The grid is 20 horizontal and 100 vertical e Results of the simulation PHOENICS when applied to this problem computes the complete two dimensional fields of concentrations of all fourteen fluids by taking into account the flow turbulent diffusion chemical reaction and coupling splitting processes The grid the parabolic mode of integration is used The Prandtl mixing length model is used for the hydrodynamics velocity vectors axial velocity micro mixing rate epke the 4 fuel rich gases f17 contours unreacted f18 contours partly reacted f19 contours reacting f20 contours fully reacted fully reacted gas contours the 4 stoichiometric gases f13 contours unreacted f14 contours partly reacted f15 contours reacting f16 contours fully reacted 3 fuel lean gases f9 contours unreacted f10 contours partly reacted f11 contours fully reacted 2 more fuel lean gases f5 contours unreacted f6 contours fully reacted uncontaminated air f1 contours mean gas density The plots of the concentration profiles of the fourteen distinct fluids are interesting but it is hard to appreciate all their implications Therefore another mode of representation has been devised by the author s colleague Liao Gan Li This shows the fluid population distributions directly both as a conventional histogram and as a randomly distributed set of blobs The following command lines create screen displays when this file is viewed through polis Otherwise the line printer plots below may be inspected Colour pictures constitute a small selection of what can be deduced from the PHOENICS calculation The FDP for the location shown by IY horizontal and IZ vertical FPD 1 FPD 2 FPD 3 FPD 4 FPD 5 FPD

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_lecs/bunsen/bunsen.htm (2016-02-15)
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  • Multi-fluid Combustion Model
    length or k epsilon would reveal but no transport equations for statistical quantities are being solved average concentration of material from the upper stream But how much upper stream fluid fluid 40 remains in its pure state Only this concentration of upper stream fluid fluid 40 Where has the rest gone What about pure lower stream fluid It also occupies very little space concentration of lower stream fluid So what lies in between 38 other fluids variously intermingled The contours for fluid 10 The contours for fluid 20 The contours for fluid 30 b Another means of representing the results The results can be processed and displayed in many different ways Particularly relevant to the theme of the present paper are the discretized probability density functions PDFs which may also be called Fluid Population Distributions ie FPDs The PDFs are on the left in the next pictures The displays on the right are reminders of how the population of fluids might be distributed in a single computational cell namely at random All the PDFs to be shown relate to a downstream section of the mixing layer where the profiles are fully developed The first relates to a location near the lower higher velocity edge of the layer The population consists almost entirely of higher velocity fluid higher velocity edge At 1 6 of the width from the higher velocity edge At 2 6 of the width from the higher velocity edge At 3 6 of the width from the higher velocity edge At 4 6 of the width from the higher velocity edge At 5 6 of the width from the higher velocity edge At a location very near the lower velocity edge c The RMS velocity fluctuations There is much information to be extracted from the FPDs All that has been used so far is the root mean square velocity fluctuation as an input to the formulae for length scale growth effective viscosity micro mixing between fluids ie coupling and splitting This MNSQ quantity is of course obtainable point wise As expected a self similar distribution is found The value along the spine of the layer is approxinately 20 which is in order of magnitude agreement with experimental data contour plot of MNSQ d The cross stream profiles The following profiles all relate to the downstream end of the mixing layer where conditions have become fully developed Fig 8 2 1 shows the population mean velocity profile while Fig 8 2 2 shows the corresponding profile of root mean square velocity fluctuations Fig 8 2 1 The population mean longitudinal velocity Fig 8 2 2 The root mean square velocity fluctuation Figs 8 2 3 and 8 2 4 show the profiles of length scale and effective kinematic viscosity which correspond to the same conditions Fig 8 2 3 The profile of the length scale Fig 8 2 4 The profile of effective viscosity Fig 8 2 5 accordingly displays the profile of the multiplier in the source term

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_lecs/mfm/mfm8.htm (2016-02-15)
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  • top-page.htm
    the top bar allow you to choose some other languages than English by way of the button on the top bar clicking thereafter on any other button in order to make your choice effective choose your working directory Learn nto use nPHOENICS by way of tutorials Study nspecial nfeatures e g multi phase flow stresses in solids In Form etc Gateways nto special napplications in engineering and science including aerodynamic

    Original URL path: http://www.cham.co.uk/phoenics/d_pc/htms/english/pc_pages/standard.htm (2016-02-15)
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  • newuser.htm
    enabling you to learn about PHOENICS systematically Ready nto nrun a selection of ready to run cases from the input file library arranged so as to enable you to execute successively Satellite for the input of data EARTH for running the executable and PHOTON or Viewer for graphical display of results CFD npro contra a general lecture about CFD delivered at a Global Education conference in 2007 which contains warnings

    Original URL path: http://www.cham.co.uk/phoenics/d_pc/htms/english/pc_pages/newuser.htm (2016-02-15)
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  • Learn panel
    POLIS The PHOENICS On Line Information System This button will take you to the top of the Information Mountain but you may prefer to start lower down for example at PHOENICS Overview or What s New in Version 3 6 PHOENICS n overview a general introduction to the PHOENICS software system latest nPHOENICS n High lights What s new in PHOENICS version 3 6 PRELUDE the new relational pre processor

    Original URL path: http://www.cham.co.uk/phoenics/d_pc/htms/english/guidance/learn.htm (2016-02-15)
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web-archive-uk.com, 2016-10-27