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| Introductory| 1 | |
| lecture 1 | ---- | The PHOENICS flow-simulation system |
| | 10 | by D. Brian Spalding |
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| * The purpose for which PHOENICS has been created: |
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| PHOENICS is intended to facilitate the employment of |
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| the techniques of Computational Fluid Dynamics, |
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| by all persons capable of understanding their nature |
| and limitations, |
| as an aid in:- |
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| * education * research |
| * engineering design * environmental science |
| * medical diagnostics * etc. |
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| Introductory| 2 | |
| lecture 1 | ---- | The main features of the PHOENICS |
| | 10 | concept |
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| PHOENICS is characterised by: |
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| * a compact and flexible language for setting up fluid- |
| and heat-flow simulations, the PHOENICS Input Language; |
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| * a computer-resident library of simulation-set-up files, |
| allowing easy storage, access, updating and transmission;|
| |
| * machine independence, so that PC's differ from Crays |
| only in speed; |
| |
| * extreme modularity, allowing users to replace physical |
| models, equation formulations, solution procedures, etc. |
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| Introductory| 3 | |
| lecture 1 | ---- | Qualities striven for by the creators |
| | 10 | of PHOENICS. These include .... |
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| * Subservience to the user (who must therefore accept some |
| responsibility for selecting models, formulations, etc.) |
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| * Robustness, ensuring that computational failures are few. |
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| * Universality, permitting anything that flows (liquid, |
| gas, viscoelastic "solid", heat, electricity, traffic) |
| to be simulated by a single computer code. |
| |
| * Expansibility, allowing users to increase the number of |
| dependent variables, boundary conditions, property variat- |
| ions, etc, without limit. |
| |
| * Longevity, promoted by attention from permanent "nurses". |
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| Introductory| 4 | |
| lecture 1 | ---- | Cans and can'ts |
| | 10 | |
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| * The PHOENICS input and output procedures interface well |
| with other computer codes for CFD, |
| EXCEPT for those employing unstructured grids. |
| |
| * PHOENICS can handle 0-, 1-, 2- and 3-dimensional problems, |
| with or without:- * time-dependence, * turbulence, |
| * compressibility, * chemical reaction, |
| * multiple phases, * curved coordinates,|
| * free surfaces, * thermal radiation; |
| BUT its solutions are subject, as usual, to numerical |
| diffusion, discretization error, etc. |
| |
| * PHOENICS has a built-in "expert" system, BUT it is embryonic
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| Introductory| 5 | |
| lecture 1 | ---- | More cans and can'ts |
| | 10 | |
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| |
| * The PHOENICS pre-processor is very flexible, and easy to |
| use by frequent users; |
| BUT beginners, and those with narrow flow-simulation |
| interests may prefer to use the "menu-driven" input system.|
| |
| * "Menu-driven" input attachments are provided for |
| these and other special-interest groups; |
| BUT not all PHOENICS features can yet be accessed thereby. |
| |
| * PHOENICS lends itself well to "learning-by-exploration" |
| methods of education; |
| BUT the collaboration of educators is needed for the |
| creation of the student-guidance programs. |
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| Introductory| 6 | |
| lecture 1 | ---- | PHOENICS as a facilitator of |
| | 10 | collaboration |
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| |
| * PHOENICS is already widely distributed through the world |
| and will spread further. It therefore already presents an |
| opportunity for distance-separated CFD practitioners to |
| communicate data-input files, reproduce results, etc. |
| |
| * The PHOENICS input library already contains hundreds of |
| input-file examples. Distant users wishing to do so can |
| supply new library entries, and have them distributed |
| worldwide by publishing them in the PHOENICS Journal. |
| |
| * New subroutines embodying turbulence-model, chemical-source|
| or other physical or mathematical novelty can likewise be |
| published in the Journal for the benefit of other users. |
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| Introductory| 7 | |
| lecture 1 | ---- | Divisions of the current library |
| | 10 | |
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| The PHOENICS input-file library is divided as follows: |
| |
| ... PHOENICS core library ... PHOENICS options library |
| 1 NEWS and Introduction (W) Two-phase (IPSA) examples |
| 2 Single-equation examples (B) Body-fitted coordinates |
| 3 One-phase parabolic flows (M) Extra multi-phase features |
| 4 One-phase elliptic flows (N) Extra numerical algorithms |
| 5 One-phase unsteady flows (C) Extra chemical reactions |
| 6 Conjugate heat transfer (R) Extra radiation features |
| 7 Chemical reaction & radiation (T) Extra turbulence models |
| 8 Equipment-oriented examples (O) Other extra features |
| |
| Users can also attach and create their own libraries. |
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| Introductory| 8 | |
| lecture 1 | ---- | The nature of library entries |
| | 10 | |
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| * Typically a library entry, for a single flow simulation, |
| consists of about 100 lines of PHOENICS input language, |
| plus as many plain-language comments as are desired. |
| |
| * Very little space is therefore occupied; so computer disks|
| can accommodate libraries for thousands of CFD simulations|
| |
| * Users can attach their own "private wings", with limited |
| access rights. |
| |
| * As well as storing data-input instructions, library files |
| can also contain sequences (as PHOTON "use" files) which |
| control the graphical display of the computed result. |
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| Introductory| 9 | |
| lecture 1 | ---- | The future of the library, |
| | 10 | and of PHOENICS |
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| * The library system can be expected to extend greatly, |
| as users recognise its utility both for themselves and |
| for those with whom they wish to communicate on matters |
| of computational fluid dynamics. |
| |
| * Since most CFD codes have to be supplied with input |
| information of the same kind, in more or less the same |
| order, the PHOENICS input language is being found useful |
| for setting up flow simulations to be performed by other |
| codes than PHOENICS, |
| |
| * The PHOENICS library system may thus finally prove to be |
| more important for CFD practitioners than PHOENICS itself.|
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| Introductory| 10 | |
| lecture 1 | ---- | PHOENICS on personal computers |
| | 10 | |
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| * PHOENICS was successfully mounted on IBM AT and compatible |
| machines in 1987. However, the 640K accessible-memory limit|
| of MS DOS then caused unwelcome degradation of performance.|
| |
| * The advent of extended memory options and later DOS versions
| have totally removed these difficulties. Mnay users now |
| work exclusively on personal computers, either with 386 or |
| 486 processors, and either of desk-top or note-book size. |
| |
| * PHOENICS is normally provided by CHAM with either the |
| Salford or the Lahey Fortran compiler. The performances |
| yielded by these compilers are approximately the same. |
| |
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