UPGRADING ARIZONA PUBLIC SERVICE/PALOVERDE NUCLEAR GENERATING STATION (PVNGS) SIMULATOR TO RELAP5/MOD3 THERMAL HYDRAULICS AND MULTI DIMENSIONAL NEUTRON KINETICS BASED ON THE NESTLE.

摘要

Limitation in the PVNGS training simulator, Reactor Coolant System (RCS) model, specifically in the lower mode operation such as reduced RCS inventory (mid-loop operation), necessitated the implementation of RELAP5 (1) into the PVNGS simulator. This enhancement also has added many benefits in the area of neutronics due to the facts that RELAP5 contains a Reactor Kinetics Model which is a multi- dimensional neutron Kinetics model based on the NESTLE (2). The Kinetics addition helped us in the areas of Axial Shape Index (ASI), azmitual tilt, rod drops, rod ejection, rod withdrawal, scram and stability. This is important for digital power plant in training operators to anticipate the plant transients, and take appropriate action to prevent a reactor trip. This paper will describe the process of implementation of RELAP5 and nodalization approach for modeling the PVNGS simulator.