Evaluation of advanced computer systems for performing system thermal-hydraulic modeling

The thermal-hydraulic code FLOC has been developed to investigate the vector and multi-CPU performance of advanced computer systems. The FLOC code solves the area-averaged Navier-Stokes equations using a semi-implicit formulation that produces a linear system in terms of the spatial pressure distribution. This code was written on a VAX and transported to a CRAY X-MP, where it was optimized for vectorization on a single CPU. Subsequently, the code has been transported to an IMB 3090 at Cornell National Supercomputer Center and to an Alliant FX/8 mini supercomputer at Argonne National Laboratory. Several nodalizations have been developed to model a typical Westinghouse four-loop pressurized water reactor