基于计算流体动力学与离散元法的离心泵内流场及磨损的数值模拟

利用离散单元法与流体动力学耦合的方法研究了不同入口流速(0.6、1.2、1.7 m/s)和额定转速(2650、2800、3000 r/min)下单级离心泵内部流场变化、磨损部位、磨损量、输送能力。结果表明：离心泵叶轮叶片尾部易发生空化现象，入口流速对叶片空化现象、出水管道滞留区域产生的影响大于转速的；9种工况下离心泵最大磨损量出现在叶片尾部，转速从2650 r/min变化为3000 r/min时，磨损最严重的部位由叶片1、4尾部变为叶片1、2尾部，叶轮叶片为离心泵磨损最严重的部件，占离心泵总磨损量的38.10%~49.41%；离心泵内沙粒平均停留时间表明，流速对离心泵输送性能的影响大于转速的，入口流速0.6 m/s、1.2 m/s、1.7 m/s下沙粒平均停留时间分别为0.144、0.068、0.052 s，说明随着流速的增加，离心泵输送性能增强。

Numerical simulation of flow field and wear in centrifugal pump based on CFD-DEM

The change of internal flow field, wear position, wear quantity and conveying capacity of centrifugal pumps were explored at different inlet speeds(0.6, 1.2, 1.7 m/s) and rotational speeds(2650, 2800, 3000 r/min) by using the method of discrete element method and fluid dynamics coupling. The results show that the tail of impeller blade of centrifugal pump is prone to cavitation, and the influence of velocity on cavitation and retention area of outlet pipe is greater than that of speed. Under nine working conditions, the maximum abrasion loss of the centrifugal pump appears at the tail of the blade. When the speed changes from 2650 r/min to 3000 r/min, the most serious wear part changes from the tail of blade 1 and 4 to the tail of blade 1 and 2. The impeller blade is the most serious wear part of the centrifugal pump, accounting for 39.36%-49.41% of the total abrasion loss of the centrifugal pump. According to the average residence time of particles in the centrifugal pump under nine working conditions, the flow rate has a greater impact on the performance of the centrifugal pump than the speed, and the average residence time of particles under 0.6, 1.2 and 1.7 m/s are 0.144, 0.068 and 0.052 s respectively, which indicated that the centrifugal pump delivery performance improved with an increase in the velocity.