Study On Screening Efficiency Of Cantilever Vibrating Screen Based On EDEM

Vibrating screen is widely used in coal industry particle size classification,the level of screening performance is related to the economic benefits of coal preparation plant.In recent years,cantilever vibrating screen because of its screening efficiency is high,stable performance,especially suitable for wet fine material screening and widely used,but the existing screening theory is for the traditional closed screen structure of the vibrating screen,for the cantilever vibrating screen screening theory is not clear enough,perfect.Therefore,the research of cantilever vibrating screen has great significance for the development of screening equipment in China.This paper summarizes the domestic and foreign scholars using the finite element method,discrete element method and discrete element method and finite element method coupling method to the study of vibrating screen,in detail elaborated the basic principle of discrete element method and contact model between particles,this paper introduces the related theory,in the process of vibrating screen points through Solid Works software to establish the geometric model of cantilever vibrating screen,own sphere fitting in with EDEM software tools to modeling of coal particles,and then the movement process of coal particles on the cantilever vibrating screen for simulation,and based on DEM and FEM coupling method.The structure of screen surface was analyzed statically.Then,the influences of the length of the sieve rod,the arrangement of the screen surface,the amplitude,the frequency,the inclination Angle of the screen surface and the vibration mode on the particle velocity and screening efficiency are discussed.Finally,a verification test is designed and carried out to verify the accuracy of the simulation results.The results show that:In a certain range,increasing the length of the sieve rod can improve the screening efficiency of the cantilever vibrating screen,but it has little effect on the average velocity of the particle group on the screen surface.Under the condition that the length of the screen rod is constant,the screening efficiency and the average velocity of the particle group on the screen surface can be improved by changing the arrangement of the screen surface.In the process of discussing the dip Angle,amplitude and frequency of the cantilever vibrating screen,with the increase of the dip Angle,amplitude and frequency of the screen surface,the screening efficiency increases first and then decreases gradually,while the average velocity of the particle group on the screen surface increases.On the basis of single factor,the experimental study of response surface was carried out,and the influences of amplitude,frequency and screen surface inclination on screening efficiency were analyzed,and a quadratic polynomial regression model with three factors and three levels of screening efficiency was established.In the process of discussing the vibration mode,it is found that the screening efficiency is the highest when the linear vibration occurs,but the average velocity of the particle groups on the screen surface is basically the same.Through the qualitative analysis of the screening test results of cantilever vibrating screen at different frequencies and the comparison of the simulation results,the feasibility of using the discrete element method to simulate the screening of cantilever vibrating screen is proved.Through the study of the screening process of the cantilever vibrating screen,it provides certain theoretical support for the improvement of the research of screening equipment,and verifies the feasibility of the discrete element method in material screening.