并联立式屏蔽电机主泵流动特性数值研究

Numerical Study on the Flow Characteristics of the Parallel Main Pumps of the Vertical Canned Motor

以缩比系数为1∶4的立式屏蔽电机反应堆主冷却剂循环泵(简称主泵)为研究对象,建立2台并联主泵反向旋转(模型1)和同向旋转(模型2)2种几何模型;运用计算流体力学(CFD)方法对2种模型的并联主泵内部流场进行稳态运行计算,从主泵的外特性、进口流动特性、入流品质、管内压力分布方面对模型1和模型2进行对比分析。结果表明,模型1中A、B主泵性能基本一致;模型2中A、B主泵的流量相对偏差基本在0.8%以内,最大值达到1.69%,扬程相对偏差稳定在1%以内,效率和轴功率相对偏差最大值分别达到6%和8%;模型2相对模型1流动稳定性更好、入流品质更高、管内压力分布较低,有利于设备的长期运行。

Taking the reactor main coolant circulation pump(referred to as the main pump)of the vertical canned motor with a scale factor of 1:4 as the research object,two kinds of geometric models with two counter-rotating parallel main pumps(model 1)and two co-rotating parallel main pumps(model 2)are established.Using computational fluid dynamics(CFD)method to calculate the steady-state operation of the internal flow field of the two models of parallel main pumps,from the external characteristics of the main pumps,the inlet flow characteristics,the inflow quality,and the pressure distribution in the pipe,the comparative analysis of model 1 and model 2 is conducted.The results show that the performance of the main pumps A and B in model 1 are basically the same;the relative deviation of the flow rate of the main pumps A and B in model 2 is basically within 0.8%,the maximum value reaches 1.69%,the relative deviation of head is stable within 1%;the maximum relative deviation of the efficiency and shaft power reaches 6%and 8%respectively;compared with model 1,model 2 has better flow stability,higher inflow quality,and lower pressure distribution in the pipe,which is conducive to the long-term operation of the equipment.