MCS – A Monte Carlo particle transport code for large-scale power reactor analysis

Abstract

A new Monte Carlo (MC) neutron/photon transport code, called MCS, has been developed at Ulsan National Institute of Science and Technology (UNIST) with the aim of performing the high-fidelity multi-physics simulation of large-scale power reactors, especially pressurized water reactors (PWR). The high-fidelity multi-physics analysis of large-scale PWR is a challenging problem due to two aspects, the first being the difficulty of implementing various state of the art techniques into a single code system, and the other making it feasible to run such simulations on practical computing machines within reasonable amount of memory usage and computing time. In this paper, features implemented into MCS for large-scale PWR simulations are described including but not limited to depletion, thermal/hydraulics coupling, fuel performance coupling, equilibrium xenon, on-the-fly neutron cross-section Doppler broadening, and critical boron search. The efficient memory usage for burnup simulation and the high performance of MCS through various algorithms and optimizations (parallel fission bank, hash indexing) are illustrated on Monte Carlo performance benchmarks. Finally, the large-scale PWR analysis capability is fully demonstrated with BEAVRS Cycles 1 & 2 calculations.