COUPLED RELAP5 AND CONTAIN ACCIDENT ANALYSIS USING PVM

This article describes the development of an integrated accident analysis capability considering both reactor vessel and containment system responses. This integrated package, which uses the RELAP5 and CONTAIN computer codes, provides the user with greater accuracy and modeling flexibility when compared with accident analyses using these codes separately. Multiprocessing, together with message-passing-based data transfer enables these concurrent RELAP5 and CONTAIN calculations. The data transfer facilitates the coupling between the reactor vessel and containment portions of the calculation, The parallel Virtual Machine software system running on a network of IBM RISC System/6000 workstations provided the multiprocessing capabilities required for this work. The results of an anticipated-transient-without-scram scenario for a boiling-water reactor nuclear power plant are provided. For the scenario analyzed the containment temperatures and pressures that were predicted on the basis of the stand-alone codes and standard analysis methods were lower (i.e., less conservative) than those predicted with the use of the integrated code package.