ANTICIPATED TRANSIENTS WITH/WITHOUT SCRAM ANALYSES USING THE PVM-COUPLED RETRAN THERMAL-HYDRAULICS AND STAR THREE DIMENSIONAL KINETICS CODES

摘要

The Parallel Virtual Machine (PVM) software [1] has been used at Pennsylvania State to couple the RETRAN-03 thermalhydraulics code [2] with the Analytic Nodal Method (QUANDRYbased) STAR [3] three-dimensional kinetics code to analyze various plant transients that require more than point or onedimensional kinetics for proper simulation. The PVM software [1] was used to couple STAR and RETRAN automatically so that a truly parallel thermal-hydraulics and three-dimensional kinetics calculation can be achieved. The analysis was performed on two linked RISC/6000 workstations with the PVM software driving the calculation and directing the coupled data information flow. Two Anticipated Transient without Scram (ATWS) events in a typical four-loop Westinghouse plant have been analyzed with the RETRAN/STAR coupled code system: (a) total loss of feedwater ATWS, and (b) station blackout, i.e., total loss of feedwater, reactor coolant pump trip, and no power operated relief valve actuations. Previous analyses [4,5] showed how RETRAN and STAR were executed in tandem, where nodal power and core thermalhydraulic inlet boundary conditions were passed manually to each code, and all phases of the transient were rerun for consistency [4]. With the advent of RISC workstations, and the PVM software, it is now possible to execute RETRAN and STAR in a truly coupled approach, without repeating portions of the event to force the core inlet boundary conditions and global power levels to be compatible.