基于广义半马尔科夫过程(GSMP)模拟方法实现点堆中子动力学方程的蒙特卡罗求解。该方法模拟裂变系统内中子数和缓发中子先驱核数目的瞬态演化过程,并计算出任意时刻裂变功率和缓发中子源强等物理量。利用本文提出的方法研究快中子增殖堆(简称“快堆”)和热堆参数下的点堆动力学方程,对反应性的阶跃输入、斜坡输入和振荡输入的点堆中子场瞬态过程进行模拟,并与传统数值算法的计算结果进行比较。该方法不存在数值计算的刚性问题,能方便地对复杂反应性输入过程进行计算,并能充分考虑瞬态过程中反应性变化对中子代时间的影响。
A Monte Carlo method based on the simulation of the generalized semi-Markov process method is described and investigated in this paper. The transients of neutron population and precursor population in the fissionable assembly are simulated by this method. The fission power and the delayed neutron source intensity at any time are obtained. The point kinetics equations of fast reactor and thermal reactor are studied by this method. The transients of reactors with step reactivity, ramp reactivity and oscillatory reactivity are simulated, which are systematically compared with the traditional numerical results. There is no stiffness problem for this method, which can conveniently simulate the complex reactivity input process, and fully consider the effect of the reactivity change on the kinetics parameters.