数值堆材料辐照损伤并行动力学蒙特卡罗软件MISA-AKMC的设计与实现

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

材料辐照损伤模拟是数值堆软件的重要内容。原子动力学蒙特卡罗(AKMC)方法是研究核材料辐照行为的重要手段,可在保持原子级别精度下,有效地扩展模拟的时间尺度到秒甚至年量级。但在面向实际应用需求时,其仍面临内存限制和复杂的计算量等挑战。通过并行计算技术提升计算效率是解决这一挑战的有效手段。本文论述一款并行AKMC程序MISA-AKMC的设计原理与实现技术。MISA-AKMC实现了一种并行KMC模拟框架,重点包括sub-lattice并行算法的实现、加速优化方法、转发通信方法、KMC模型接口等。基于该框架,开发了空位-间隙的演化模型,可实现热老化模拟和析出模拟。通过并行性能测试获得了良好的并行性能,结合算例结果验证说明了MISA-AKMC的正确性和可靠性。

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.