蒙特卡罗粒子输运问题的全局降方差方法  

Global Variance Reduction Method for Monte Carlo Particle Transport Problemes

作　　者：许海燕[1] 黄正丰[1] 蔡少辉[1] 

机构地区：[1]北京应用物理与计算数学研究所,北京100094

出　　处：《计算物理》2010年第5期722-732,共11页Chinese Journal of Computational Physics

基　　金：中国工程物理研究院科学技术面上基金(20060649)资助项目

摘　　要：精确获得中子通量的时间-空间-能量精细分布对于一类非定常粒子输运蒙特卡罗模拟至关重要.以零方差理论为基础,采取化整为零的策略,把蒙特卡罗方法与离散纵标方法相耦合,用近似重要函数指导蒙特卡罗模拟,给出一种实现蒙特卡罗全局降方差的计算方案.数值算例表明,该计算方案获得了全局降方差的效果.A global variance reduction method is described. The method is based on a modified transport problem that can be solved by analog Monte Carlo with zero variance. It is developed by breaking up the whole into parts and coupling Monte Carlo method with discrete ordinates method and using approximate importance function to guide Monte Carlo simulation. Performance of the method for a one-dimensional sphere transport problem is demonstrated. The method is shown to produce lower variances globally compared to analog Monte Carlo.

关 键 词：蒙特卡罗方法 粒子输运 离散纵标方法 伴随计算 全局降方差 

分 类 号：O242.1[理学—计算数学]