光棒束轴向交混特性的数值模拟研究  

Numerical Simulation Study on Axial Mixing Characteristics of Rod Bundles

作　　者：张晓阳 赵民富[1] 魏君翰 段明慧[1] 许永旺 ZHANG Xiaoyang;ZHAO Minfu;WEI Junhan;DUAN Minghui;XU Yongwang(Reactor Engineering Technology Research Institute,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《中国核电》2024年第2期210-217,共8页China Nuclear Power

摘　　要：为了准确预测燃料组件出口上游的临界状况,提高安全分析的可靠性,采用CFD方法对光棒束子通道间的流动交混进行研究。对光棒束建立模型,选取SST模型进行计算,完成网格敏感性分析,在额定工况下得到轴向不同位置的子通道温度分布。利用子通道分析程序与数值模拟数据相配合,共同确定光棒束轴向不同位置的交混系数。计算结果表明:如果将入口处的交混现象视为局部交混,可以发现当局部交混影响减弱,随着轴向长度的增加,交混系数呈现出逼近0的趋势;选取16个中心通道和选取全部子通道计算所得的轴向交混系数无太大差别;入口处的交混是由于热边界层发展造成的,并非是由于入口处流量分配造成。To accurately predict the critical condition at the upstream of the fuel assembly outlet and improve the reliability of safety analysis,this paper uses the CFD method to study the flow mixing between subchannels of rod bundles.A geometric model for the rod bundles is established,the SST model for calculation is selected,the mesh sensitivity analysis is completed,and the temperature distribution of subchannels at different axial positions under rated operating conditions is obtained.Using the subchannel analysis program in conjunction with the numerical simulation data,the mixing coefficients at different axial positions of rod bundles are determined.The calculation results indicate that if the mixing phenomenon at the entrance is considered as local mixing,it can be observed that when the influence of local mixing weakens,the mixing coefficient shows a trend of approaching 0 with the increase of axial length.There is no significant difference in the axial mixing coefficient calculated by selecting 16 central channels and selecting all subchannels.The mixing at the entrance is caused by the development of the thermal boundary layer,not by the flow distribution at the entrance.

关 键 词：数值模拟 轴向交混系数 子通道分析程序 

分 类 号：TM623[电气工程—电力系统及自动化]