An Improved One-and-a-Half Group BWR Core Simulator for a New-Generation Core Management System
An Improved One-and-a-Half Group BWR Core Simulator for a New-Generation Core Management System
复制标题
一种改进的新一代堆芯管理系统的半群沸水堆堆芯模拟器
DOI：
10.1080/18811248.2000.9714864
复制
发表时间：
2000
影响因子：
1.2
通讯作者：
M. Yamamoto
中科院分区：
文献类型：
--
作者：
T. Iwamoto;M. Yamamoto
针对下一代沸水堆堆芯管理系统，提出了一种改进的一组半堆芯模拟方法。在改进的方法中，节点内的光谱指数（热快通量比）扩展与解析解的扩散方程，并计算节点的功率密度和接口的净电流，考虑到节点内的通量形状。开发了一种独特的组装非均匀性校正方法。因此，消除了传统的一个半组的方法的不确定性，我们可以有准确的功率分布，以及燃料组件之间具有较大的光谱失配的核心的局部峰值因子。在节点功率和局部峰化计算中也考虑了频谱失配的历史影响。虽然反射器没有明确解决，基本上是没有必要的核心相关的可调参数，因为边界条件是在内部节点相同的方式得出。节点解的计算时间与传统方法相当，不到少组节点模拟器的1/10。通过与非均匀细网格多群堆芯耗尽计算结果的比较，验证了该方法的准确性。
An improved one-and-a-half group core simulator method for a next-generation BWR core management system is presented. In the improved method, intranodal spectral index (thermal to fast flux ratio) is expanded with analytic solutions to the diffusion equation, and the nodal power density and the interface net current are calculated, taking the intranodal flux shape into consideration. A unique method was developed for assembly heterogeneity correction. Thus eliminating the insufficiencies of the conventional one-and-a-half group method, we can have accurate power distributions as well as local peaking factors for cores having large spectral mismatch between fuel assemblies. The historical effects of spectral mismatch are also considered in both nodal power and local peaking calculations. Although reflectors are not solved explicitly, there is essentially no need for core dependent adjustable parameters, since boundary conditions are derived in the same manner as in the interior nodes. Calculation time for nodal solutions is comparable to that for the conventional method, and is less than 1/10 of a few-group nodal simulator. Verifications of the present method were made by comparing the results with those obtained by heterogeneous fine-mesh multi-group core depletion calculations, and the accuracy was shown to be fairly good.