SAS4A LMFBR whole core accident analysis code

Abstract

To ensure that public health and safety are protected even under accident conditions in an LMFBR, many accidents are analyzed for their potential consequences. Extremely unlikely accidents that might lead to melting of reactor fuel and release of radioactive fission products are referred to as hypothetical core disruptive accidents (HCDAs). The evaluation of such accidents involves the simultaneous evaluation of thermal, mechanical, hydraulic and neutronic processes and their interactions. The complexity of this analysis requires the use of large, integrated computer codes which address the response of the reactor core and several important systems. The SAS family of codes, developed at Argonne National Laboratory, provides such an analysis capability. The SAS4A code, the latest generation of this series of codes, has recently been completed and released for use to the LMFBR safety community. This paper will summarize the important new capabilitites of this analysis tool and illustrate an application of the integrated capability, while highlighting the importance of specific phenomenological models.