Study On The Influence Of Particle Shape On DEM Numerical Simulation To Screening

Screening is one of the most widely used material classification methods and widely used in agriculture,medicine,food,construction,minerals and other industrial fields.Screening performance affects the actual production process directly.Numerical simulation method as an important and effective approach for the study of sieving process,have provided an efficient way for investigating the theory of vibrating sieving and complicated sieving process.Particle shape plays a key role in the numerical simulation analysis,the effect of particle shape on the numerical simulation results has been widely concerned by scholars at home and abroad in recent years.So far,there is still a lack of systematic study of particle shape on the law of screening simulation results.Therefore,this thesis presents a systematic numerical simulation of the vibration sieving process use non-spherical particles based on the three-dimensional discrete element method,and explore the effect of particle shape on the law of screening numerical simulation results.The main contents are as follows:1.The non-spherical particles whose shape and sharpness changed gradually were established as feed particles in the numerical simulation respectively,on the basis of study of non-spherical particle modeling theories and characterization methods.2.The three-dimensional vibrating screen model of translational and oscillating composite vibrations was established,and EDEM software based on DEM was choose to simulate the screening process of spherical and non-spherical particles.The curve law of screening efficiency per unit time was obtained under different shape feed particles and same screening parameters.The sieving mechanism of different shape feed particles was investigated,and based on the statistical variance analysis,we found that particle shape had a strong influence on the screening efficiency per unit time.3.This thesis designed a series of numerical simulations of different vibration parameters and different shapes of feed particle for revealing the influence of particleshape on the relationship between vibration parameters and sieving efficiency per unit time.By means of statistical data processing method,the relationship between the sieving parameters and the sieving results was not significant in the numerical simulation.These conclusions laid the foundation for correcting the experimental data of screening simulation results of different feed particles.