直接使用CAD几何的蒙特卡罗粒子输运方法研究

Research on Monte Carlo Particle Transport Method Directly Using CAD Geometry

传统的蒙特卡罗程序通常使用构造实体几何(CSG)的方法进行几何建模。然而对于某些复杂的高阶曲面使用CSG进行精确建模非常困难且会耗费大量的时间。为解决这一问题,国际上提出了一种直接使用CAD几何建模的蒙特卡罗(DAGMC)方法来进行粒子输运计算。本文基于反应堆蒙特卡罗程序RMC,开发了使用CAD几何的DAG-RMC程序,并将DAG-RMC应用于方块组合体、燃料棒和犹他州茶壶3种模型的计算分析。结果表明:DAG-RMC的计算结果与传统CSG建模方法及OpenMC程序的结果符合良好,验证了DAG-RMC在粒子输运及临界计算中的正确性。

Constructive solid geometry(CSG)is usually used to model in traditional Monte Carlo programs.However,it is very difficult and time-consuming to use CSG to accurately model some complex high-order surfaces.In order to solve this problem,a Monte Carlo method(direct accelerated geometry Monte Carlo,DAGMC)that directly used CAD geometric modeling was proposed to perform particle transport calculations.Based on Monte Carlo program RMC,the DAG-RMC program using CAD geometry was developed,and three models of block assembly,fuel rod and Utah teapot were calculated and analysed using DAG-RMC program.The results show that the calculation results of DAG-RMC are in good agreement with the results of the traditional CSG modeling method and OpenMC program,verifying the correctness of the DAG-RMC in particle transport and critical calculation.