CEFR流量1区燃料组件管脚流量分配数值模拟

Numerical Simulation of CEFR Fuel Assembly Pin Flow Distribution in Flow 1 Zone

为提高堆芯流量分配的精度,通过CFD数值模拟软件CFX,应用标准k-ε湍流模型及SIMPLE算法对中国实验快堆1型小栅板联箱、节流件及流量1区管脚的流量分配进行三维数值模拟。在已有研究基础上,模拟过程中考虑了材料的壁面效应对压降的影响,使模拟工况更接近实验真实情况。与已有实验结果进行对比时,考虑了重力压降、沿程压降及局部压降,对模拟结果进行了系统误差修正。由计算结果可知:节流件及小栅板联箱的压降计算结果与修正后的水力台架实验结果符合较好。在本文的管脚布置情况下,1、5、6号组件的平均流量比2、3、4、7号组件的平均流量低3.8%。根据模拟计算结果可更准确地预测堆内最热管的流量分配情况,可为今后的水力实验提供参考。

In order to improve the precision of the reactor core flow distribution , the CFX code was used to simulate the three-dimensional flow through type-1 throttle structure ,throttle structure and flow 1 zone pin in China Experimental Fast Reactor based on standard k-εturbulence model and SIMPLE algorithm .The effect of the wall surface of the material on the pressure drop was taken into account during the simulation process in order to further approach the real situation in the experiment .The gravity pressure drop and pressure drop along the path as well as the local pressure drop were regarded as experimental system error correction when the numerical results were compared with the available experimental results .The results show that the simulation results and experimental results after reasonable correction are in good agreement .The average outlet flow in pin 1 ,5 and 6 is 3.8% lower than the average outlet flow in pin 2 ,3 ,4 and 7 .Not only the flow distribution in the hottest tube can be more accurately determined ,but also the reference for the future hydraulic bench test is figured out according to the simulation results .