Multi-Group Constants Generation System for 3D-Core Simulation Using a Continuous Energy Monte Carlo Technique

Abstract

method is a powerful and flexible approach for calculating heterogeneous fuel designs with the aim of developing innovative fuel and core concepts, as the calculation precisely handles both the geometrical configurations of a fuel assembly and the contained materials therein. However, a whole-core Monte Carlo burn up calculation has not been feasible, because it requires large scale computing resources and time. Instead, a combination of a Monte Carlo method and a conventional deterministic method is more applicable. The continuous energy Monte Carlo technique is used to generate the multi-group constants of a fuel assembly for a three-dimensional core simulation, which uses a conventional deterministic method. We have developed a multi-group constants generation system for a three-dimensional core simulator using the results of a continuous energy Monte Carlo simulation with reasonable computation time. We also performed a transient calculation based on the three-dimensional core simulation made by the system. We have performed verification analyses of the system using current BWR fuels and a BWR core configuration. Compared with the current method, namely a multi-group constants generation system using the results of a deterministic lattice physics code, the result of the newly developed system has shown good compatibility with the current system on both core performance simulations and plant transient simulations.