不连续因子计算强吸收体区域的改进

在球床高温气冷堆控制棒计算过程中，采用局部均匀化和不连续因子修正的扩散方法可取得较好的计算效果，但对具有强吸收性的吸收球区域的效果相对较差。经研究发现，在强吸收体模型中，强吸收体对附近石墨区域的中子通量分布仍具有较大影响，体现出扩散方法对强吸收体的不适应。因此，本文提出改进方案，不但计算吸收体区域边界处的不连续因子，且计算临近石墨区域的边界不连续因子。数值计算结果表明，改进方案可改善计算精度，在扩散计算框架下可达到精细结构的输运计算精度。

Improvement of Discontinuous Factor for Strong Absorber Region

The local homogenization plus the discontinuous factor corrected diffusion method was adopted for the control rod calculation of the pebble bed high temperature gas cooled reactor, and was proven to be effective. But the result for the small absorber ball region with strong absorber is not good enough. The investigation shows that the strong absorber still has a great influence on the flux distribution of the nearby graphite region, which is not capable for normal diffusion method. The improved calculation procedure was proposed, not only to calculate the discontinuous factor of the absorber region, but also to calculate the discontinuity factor of the neighboring graphite region. The numerical result demonstrates that the improved performance and the accuracy of transport calculation based on fine heterogeneous model can be achieved in the diffusion calculation framework.