tor Radial squeeze factor
11. Checklist of best practice advice for industrial CFD
11.14. Guidelines on communication with code developer 1. Guidelines for the code developer and vendor
¾ The code developer or code vendor needs to demonstrate that he has applied stringent methods of quality control of the software development and maintenance.
¾ Verification of the code is to be carried out by the code vendor or developer, and he should pro-vide the necessary information on the verification process for the user.
¾ The code developer or code vendor should maintain and publish a databank of verification test cases that are used for testing. The cases should include simple code verifications tests (e.g. that solutions are independent of co-ordinate systems).
¾ The code developer or code vendor should provide documentary evidence of the verification tests that the software has undergone, which should include clearly details of the code options which are used during testing.
¾ For all new versions of the code and all new machines a standard set of verification test cases should be repeated.
¾ Code vendors and code developers should supply a list of known bugs and errors in each version of the code (hot-line, password secured web-page). This list should demonstrate that the number of bugs reduces as the code matures.
¾ The code developers should try to include warning notices and guidance for the user in the output.
For example, when basic rules on grid generation (expansion ratios, skew, etc.) are being broken, when important specific default options are being overruled by the code input data or when the near wall grid is inconsistent with the turbulence modelling.
11.14.2. Guidelines for the code user
¾ Read the release notes issued by the code supplier, as these are a good source of information on changes to the code to remove existing bugs.
¾ Recognise that codes can only be validated and verified for a class of problems involving specific variables. If the application involves an area where the code is not fully verified there is more risk of code errors.
¾ Set up a suite of test cases that can be run on new code releases to provide an independent check on the code and to highlight any changes between releases (for example in default parame-ters).
¾ Check that the release version of the code is compatibility with any user defined routines, if appli-cable.
¾ When a code error is suspected, communicate this to the code vendor or developer as soon as possible, especially if no list of known bugs has been published. Other users may then profit from this experience. If the bug is well-known a solution or work-around may already be available.
¾ In any communications with the code developer or code vendor about a suspected program error, provide a short concise description of the problem and all the necessary input data files so that the error can be reproduced. In cases where commercial sensitivity precludes this, special arrange-ments will need to be made.
¾ Contact the code developer if the meaning and definition of variables in the manuals are unclear and if support is needed in the implementation of special features.
12. Acknowledgements
The material presented in this document is a real team effort and thanks are due to the many people and organisations that have co-operated in its preparation, but in particular to the management and staff of the code developers and code vendors who have encouraged and supported the work, to the academic experts who have corrected some elementary mistakes of the editors, and the many CFD users from industry who have freely shared their experience in the use of CFD.
The production of the guidelines was organised by the Fluid Dynamics Laboratory of Sulzer Innotec, Ltd. in a contract issued by the ERCOFTAC SIG (Special Interest Group) on Quality and Trust in In-dustrial CFD. The major organisational and editorial work in association with the document and its preparation was carried out by the project leader at Sulzer Innotec, Dr. Michael Casey, assisted by Torsten Wintergerste.
The first version of the best practice guidelines was produced in May 1999 with major input from the following persons: Dr. G. Scheuerer, Dr. F. Menter, Dr. J. Ferreira and Dr. S. Phillipson of AEA Tech-nology, Dr. F. Mendonca of Computational Dynamics, Dr. M. Rabbitt of British Energy, Prof. M. A.
Leschziner of University of London, Prof. I. Castro of the University of Surrey, Dr. C. Lea of HSE, Dr.
S. Gilham of WSA, Dr. N. Hakimi of Numeca, Dr. P. Wild of Fluent and Dr. M. Casey, Dr. E Lang, Dr.
P. Holbein, Dr. M. Wehrli and T. Wintergerste of Sulzer Innotec.
The first version was reviewed and improved at a technical Workshop held in Zurich on June 21 and 22, 1999. The following invited persons were present, giving coverage of both academic and industrial points of view from a range of applications, levels of experience, and European countries: Dr. M. Ca-sey, Dr. E. Lang, Dr. P. Holbein, Dr. M. Wehrli, T. Wintergerste, Miss E. Wiederkehr of Sulzer Innotec, Dr. E. Benz (ABB), Dr. J. Vos (EPFL), Prof. A. Hutton (DERA), Dr. C. Carey (Alstom), Dr. A. Kelsey (HSE), Dr. N. Rhodes (Mott Macdonald), Dr. S. Gilham (WSA), Dr. P. Tucker (NAFEMS), Dr. P. An-dreasson (Vattenfall Utveckling), Prof. Ch. Hirsch (VUB), Prof. W. Rodi (Karlsruhe), Dr. F. Klimetzek (Daimler Chrysler Cars), Dr. W. Haase (Daimler Chrysler Aerospace), Dr. F. Archambeau (EDF), Dr.
H. Paillere (CEA), Dr. F. Mendonca (CD), Dr. S. Phillipson (AEA), Dr N. Hakimi (Numeca) and Dr. P.
Wild (Fluent). Many other persons offered their services for the workshop but could not take part either because numbers were limited or because the date was unsuitable.
An interim version based on the input from the workshop was produced by Sulzer Innotec for final edit-ing, with particularly high quality and helpful input to chapter 3 from Dr. Marc Wehrli (Sulzer Innotec) and to chapter 4 from Prof. Tony Hutton (DERA). Helpful revisions to the interim version were received from Dr. P. Andreasson (Vattenfall Utveckling), Dr. C. Lea and Dr. A. Kelsey (HSE), H.-D. Grein (NEC), Dr. P. Holbein (Sulzer Innotec), Dr. H. Pailliere (CEA), Dr. M. Rabbitt (British Energy) Dr P.
Drtina and Dr. H. Keck (Sulzer Hydro), Prof. Ch. Hirsch (VUB), Prof. I. Castro (Surrey University), Prof.
W. Rodi (Karlsruhe University), Dr. W. Haase (Daimler Chrysler Aerospace), Dr. F. Archambeau and Dr. N. Gay (EDF), Dr. S. Phillipson, Dr. G. Scheuerer and Dr. F. Menter (AEA).
A draft of the final version was prepared for the ERCOFTAC SIG meeting in Florence at the end of October 1999. After this meeting, some additional revisions of the chapter on turbulence modelling were received from Prof. Ian Castro, Dr. Georg Scheurer, Prof. Mike Leschziner and Prof. Tony Hutton, and these were incorporated into the final version.
The test cases were calculated by the code vendors and code developers whose names appear in the sections of chapter 9. Sulzer Innotec and the ERCOFTAC SIG extend many thanks to the manage-ment and staff of the code developers and code vendors who have encouraged and supported the work in this way. Individual thanks go to Dr. F. Mendonca, Dr. F. Archambeau, Dr. H. Pailliere, Dr. M.
Rabbitt, Dr. N. Hakimi, Dr. P. Wild, Dr. G. Scheuerer and Dr. J. Stokes
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