基于特征线法计算的超细群慢化方程求解方法

为实现对复杂几何、复杂能谱组件的精细计算，提出了一种基于特征线的超细群慢化方程求解方法。通过耦合特征线法中的固定源计算，在共振能量范围内建立超细群慢化方程，通过精细能谱获得复杂结构下的共振自屏截面。对典型压水堆栅元问题、带有温度分布的栅元问题、燃料内部存在不均匀性的栅元问题以及板状燃料组件问题进行了计算。结果表明，基于特征线的超细群慢化方程求解方法可精确计算复杂几何、复杂能谱问题，为共振计算提供基准。

Method for Solving Ultra-fine-group Slowing-down Equation Based on Method of Characteristic

A method for solving the ultra-fine-group slowing down equation based on the method of characteristic was proposed to realize the rigorous resonance calculation of the lattices with complicated geometries and neutron spectra. By coupling the fixed source calculation of the method of characteristic, the ultra-fine-group slowing-down equation was established within the resonance energy range, and the resonance self-shielding cross sections were obtained through the ultra-fine-group neutron spectrum. The problems including the typical PWR pin-cell problem, the pin-cell problem with temperature distribution, the pin-cell problem with intra-pellet fuel division and slab fuel assembly problem were performed. The results show that this method can obtain high accuracy on complicated geometry and complicated neutron spectrum problems, providing a reference for resonance self-shielding calculation.