堆芯燃料组件流阻特性模块式与整体式三维数值模拟方案比较

组件的阻力特性影响堆芯不同类型组件的流量分配，对堆芯的设计起到至关重要的影响。为提高验证堆芯燃料组件特性的求解精度及效率，本文针对燃料区6类燃料组件中的两类进行模块式及整体式三维数值模拟，获得了两类组件的流阻特性，并用相同条件下的全组件试验结果进行了对比。结果表明：推广至堆芯所有燃料组件流阻特性预测，模块式所需计算时间约为整体式的1/6，但整体式三维数值模拟所得压降与试验结果吻合度高，误差较模块式小。最后深入研究了流速及温度变化对流阻特性的影响。该研究为后续各类组件的流阻特性研究方法选取提供技术支持。

Comparison of Modular and Integral Three-dimensional Numerical Simulation Schemes for Flow Resistance Characteristic of Core Fuel Assembly

The resistance characteristics for the assemblies affect the flow flux distribution for the different types of assemblies in the core, which has a crucial effect on the design of the core. In order to improve the calculation accuracy and efficiency of the flow resistance characteristics for the core fuel assemblies, two types of assemblies among the six types fuel assemblies in the fuel zone were conducted by modular and integral three dimensional numerical simulation in this paper, so as to obtain the flow resistance characteristics of these two types of assemblies. The simulated results were compared with the experimental results of the full assemblies under the same conditions. The results show that the calculation time required for the modular simulation is about 1/6 of the integral simulation when predicting the flow resistance characteristics of all fuel assemblies in the core, but the pressure drop of the integral three dimensional numerical simulation is more consistent with the experimental results, and has the smaller simulated error. Finally, the effect of velocity and temperature to resistance characteristics was deeply studied to provide technical support for the scheme selection for studying the flow resistance characteristics of various assemblies in the core.