Design and Implementation of Parallel Kinetic Monte Carlo Software MISA-AKMC for Material Radiation Damage in Numerical Reactor

Material radiation damage simulation is an important part of the numerical reactor software. The atomic kinetic Monte Carlo (AKMC) method plays a significant role for studying the irradiation behavior of nuclear materials. AKMC method can effectively extend the simulation temporal scale to seconds or even years with atomic-level accuracy. However, it still faces challenges on memory limitation and expensive computation in practice. Using parallel computing technology to improve computing efficiency is an effective approach to solve those challenges. The design and implementation of parallel AKMC program MISA-AKMC were preseneted. MISA-AKMC implements a parallel KMC simulation framework, focusing on the sub-lattice parallel algorithm, acceleration optimization methods, forwarding communication methods and KMC model interfaces, etc. Based on this framework, a vacancy-interstitial evolution model was developed, which can realize the thermal-aging and precipitation simulation. Good parallel performance was obtained through the parallel performance test, and the verification results from calculation examples show the correctness and reliability of MISA-AKMC.