Numerical Study On Erosion Of The Centrifugal Pump Caused By Coal Particles

The working medium,plays a significant part in the centrifugal pump,entails certain performance changing of centrifugal pumps including head and efficiency.The vast majority of fluids in nature are multiphase flows such as the coal-slurry containing coal and other solid particles,which emerged in the actual production process of coal mines.The presence of these solid particles have a great impact on the operation of centrifugal pumps,making the performance of centrifugal pumps deviate from the design condition,causing certain erosion of the centrifugal pump blade.This paper studied the erosion of the centrifugal pump in the laboratory under different conditions using CFX.The main contents are as follows:(1)The Euler-Lagrange method was used to calculate the two-phase flow in the centrifugal pump.The force of the coal particles in the centrifugal pump was simplified,and the coupling between the coal particles and the fluid was briefly introduced.The collision and the wear model used in the numerical calculation were briefly introduced.(2)The model and mesh of the centrifugal pump were carried out.In addition,the accuracy of the model was verified by comparing the calculated results with the design value of the centrifugal pump.Based on this,the internal pressure field and velocity field of the model centrifugal pump were analyzed.(3)The internal flow field and erosion of the centrifugal pump under two-phase flow conditions were studied,and the erosion of the centrifugal pump under different coal particle concentration,size and density was obtained.The results show that the higher the particle concentration is,the more serious the erosion is;the larger the particle size,the more serious the erosion of the rotor,the lighter the stator erosion is,and the lighter the total wear is;the higher the density is,the more the rotor wears,the lighter the stator wears,and the lighter the total wear is.(4)The impeller structure of the centrifugal pump was optimized,and the erosion of the centrifugal pump at different rotor outlet angles and inlet angles of the stator were studied.The internal flow and erosion of the centrifugal pump under different structures was obtained.Combining the head and efficiency of the centrifugal pump,a more suitable rotor outlet angle(22.5°)and stator inlet angle(165°)were obtained.