Implementation of a New DTSTEP Algorithm for use in RELAP5-3D and PVMEXEC Completion Report

[摘要] The PVM Coupling methodology for decomposing a complex model into domains onto which individual programs may be applied has proven effective for solving many multi-physics problems. There have been, from the outset, some detailed and/or long-running models that cause the process to fail. This project addressed the PVM coupling issues surrounding the DTSTEP subroutines on RELAP5-3D and PVMEXEC. Some 25 errors are listed in Tables 1 and 18 and in Section 11. These arise from deficiencies in the floating point calculation and testing of time steps, cumulative time, and time targets. The algorithmic replacement of floating point control of these items with integer based timestepping was developed and implemented. The result of the first phase, undertaken by the INL was that all but three of these issues were resolved. Moreover, two conceptual errors in DTSTEP that were not PVM coupling related were discovered and solved. The final, and most difficult three PVM Bettis User Problems, were solved during the Bettis phase of development and debugging. In 8 months since the conclusion of the project, no further DTSTEP related PVM Coupling errors have been reported.

[发布日期] 2010-12-01 [发布机构] Idaho National Laboratory

[关键词] 97 Mathematics And Computing Code Coupling;Pvm (Parallel Virtual Machine);Relap5-3D;Code Coupling;Integer Timestep