Research of grinding efficiency and main duct wear of pendulum mill based on CFD-DEM co-simulation

Pendulum mill is a widely used grinding equipment in powder processing industry. Less in-depth studies have been carried out especially for grinding efficiency and wear. Through theoretical analysis, the main influencing parameters were screened, among which spindle speed and spade degree mainly affect the grinding efficiency, but wind velocity mainly causes the main duct wear. The Fluent-DEM co-simulation method is used for the study of the complex physical field of mill operation. The simulation shows that grinding efficiency increases with spindle speed, but the increase from 110 to 120 rev/min is not significant, so the choice of spindle speed should consider both grinding efficiency and energy consumption. The spade degree determines the spade position, the closer the spade is to the grinding roller, the higher the grinding efficiency. Wind velocity has little effect on grinding efficiency, but it does affect the likelihood of particles entering the main duct and causing wear. Multi-objective optimization determines a spindle speed of 110 rev/min and a spade angle of −12° at a wind velocity of 46 m/s to achieve maximum grinding efficiency and minimum wear. This study provides a digital analysis basis for optimizing the operating parameters of the pendulum mill.