通量展开节块法求解六角形几何二维中子扩散方程  

Flux Expansion Nodal Method for Neutron Diffusion Calculation in Two-Dimensional Hexagonal Geometry

作　　者：夏榜样[1] 谢仲生[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2005年第7期762-765,共4页Journal of Xi'an Jiaotong University

摘　　要：提出了一种在二维六角形几何节块内数值求解中子扩散方程的节块法,节块内的各群通量分布用解析基函数近似展开,节块之间采用面偏流0次矩和1次矩进行耦合.为了提高计算效率,将响应矩阵技术应用于迭代求解过程.该方法不仅避免了常规方法中偏通量积分出现的奇异项问题,而且具备重构六角形几何节块内精细功率分布的能力.基于提出的模型,发展了二维六角形组件中子扩散计算程序FEMHEX.通过对水水动力反应堆基准问题的校验计算表明,该方法能高效、准确地给出有效增值因数及节块功率.A new flux expansion nodal method for the two-group nodal diffusion calculation in the hexagonal geometry was proposed. The neutron flux distributions within a node were expanded in a series of analytic basis functions for each group. Nodes were coupled each other with both the zero-and first-order partial current moments simultaneously. The response matrix technique was used for the iterative solution of the nodal diffusion equations, which gives a fast-running scheme for the diffusion calculations. By this method, the singular terms occurring in the transverse integration methods for hexagonal geometry can be avoided and the pin power reconstruction in the nodes can be automatically accomplished. Based on the proposed model, the code FEMHEX was developed. This method was tested against two-dimensional hexagonal benchmark problems for the VVER-type reactors. The numerical results show that the core multiplication factor and nodal powers are predicted accurately.

关 键 词：六角形几何 中子扩散方程 节块法 解析基函数 

分 类 号：TL329.2[核科学技术—核技术及应用]