不连续因子应用于高温气冷堆三维扩散计算  

Discontinuity Factor Applied in Three-Dimensional Diffusion Calculation for High-Temperature Gas-Cooled Reactor

作　　者：周旭华[1] 李富[1] 王登营[1] 颜见秋[1] 韩松[1] 

机构地区：[1]清华大学核能与新能源技术研究设计院,北京100084

出　　处：《原子能科学技术》2009年第3期237-241,共5页Atomic Energy Science and Technology

基　　金：国家自然科学基金资助项目(10675071)

摘　　要：高温气冷堆的三维燃耗计算、三维控制棒价值计算、堆芯功率重构以及芯外探测器响应分析都必须通过三维计算实现。由于高温气冷堆侧反射层中控制棒与吸收球区均为强吸收体,因此,在该区域无法直接用扩散方法计算,而用输运方法实现三维计算又过于耗时。根据不连续因子理论,利用二维(R,θ)几何下输运-扩散耦合计算,实现控制棒与吸收球区的局部均匀化,求得不连续因子和均匀化截面。在此基础上,实现带不连续因子的三维扩散计算。计算结果表明:常规的扩散计算会带来误差,采用不连续因子修正的扩散计算,不但对中子注量率分布改善明显,对本征值、控制棒价值等的改善也很明显,可逼近精细的输运方程的结果,而计算量明显减少。带不连续因子修正的扩散计算是实现高温气冷堆三维计算的有效途径。Three-dimensional calculation is needed tor （HTGR） to realize three-dimensional burn-up for high-temperature gas-cooled reaccalculation, three-dimensional control rod calculation, power distribution reconstruction and ex-core detectors response analysis and etc. Because of the strong absorber in control rods and absorber balls region, the diffusion method can not be used directly. But transport method for detailed 3D model is very time-consuming. This paper proposes the procedure to homogenize the control rod region based on discontinuity factor theory, to calculate homogenized cross section and discontinuity factor by coupling 2D transport and diffusion calculation, then to realize 3D full core calculation with diffusion method corrected by discontinuity factor. It is shown through verification calculation that normal diffusion calculation is impossible to get accurate solution, and diffusion calculation corrected by discontinuity factor can reproduce the detailed transport solution not only in the neutron flux distribution but also in the eigenvalue and control rod worth, with much less computation time. Therefore the diffusion method with discontinuity factors is a nice solution to realize the threedimensional calculation for HTGR.

关 键 词：高温气冷堆 不连续因子 三维 控制棒 均匀化 

分 类 号：TL329[核科学技术—核技术及应用]