临界-燃耗耦合计算方法

Coupled calculation method of criticality and burnup

基于蒙特卡罗模拟方法,采用MCNP的多群计算程序模拟中子输运方程,并与栅元均匀化程序WIMS耦合,实现了临界-燃耗耦合计算。具体过程是:首先扩展MCNP的多群功能,将其能群扩展为69群;然后,由接口程序将WIMS程序产生69群共振、自屏宏观中子截面转化为ACE格式的多群截面;其次,将新产生的多群截面提供给MCNP,完成临界-燃耗计算;最后,利用此耦合程序进行了基准题校核计算以及实验对比。计算结果表明,此耦合程序是可靠和正确的。

Based on Monte Carlo simulation method, we apply the multigroup calculation code of the MCNP to simulate the- neutron transport equation. A coupled code of the MCNP code and the lattice homogeneous code WIMS is proposed to realize the coupled calculation of criticality and burnup. The specific process is as follows： firstly, the energy group is extended to 69-group owing to the extension of the multigroup calculation character of the MCNP code; secondly, we utilize the interface program to generate 69-group resonance and to transform the self-shield macroscopic neutron cross-section produced by the WIMS code into the multigroup cross-section of ACE format~ thirdly, the new cross-section is supplied to the MCNP to finish criticality and burnup calculatiom lastly, we use the coupled code to simulate benchmarks and the opposite experiment. The results indicate that the coupled code is correct and rational.