Simulation Of Particle Flow Motion Process And Study On Particle Size Separation Mechanism

In nature,particle flow is a major form of movement in natural disasters such as debris flow,collapse,and landslides.These geological hazards,which move in the form of particle flow,are highly mobile,with consequences that seriously threaten the safety of people’s lives and property.Therefore,it is of great significance to explore the movement and law of particle flow for the development of natural environment and society.Due to the complexity of the particle flow motion,it is necessary to conduct a deeper study on the motion mechanism of particle flow and the mechanical mechanism of complex phenomena including particle size separation.This paper mainly uses the discrete element method to conduct the following studies on the particle flow:Firstly,select a typical particle flow test and use numerical experiments to achieve the calibration of micro parameters,so that the simulation results are in good agreement with the test conditions,and then the reduction of the particle flow test motion process is achieved.Based on this,different graded particle flow motion models are established.From the characteristics of particle size distribution,in the vertical direction,The particles with larger particle size gradually move to the upper free surface under the effect of the particles with smaller particle size,and the particles with smaller particle size gradually aggregate downward.In the horizontal direction,the relative displacement of the particles with larger particle diameters is larger,and the relative displacement of the particles with smaller particle diameters is smaller,thereby forming characteristic particle size distribution characteristics.Secondly,based on the equal-size particle flow test model,a tracking large particle model is set up to investigate and analyze the velocity,force situation and contact between the particles when the large-size particles are in different positions.During the movement,the set large-sized particles are comprehensively expressed as forward and upper surface movements in the action of surrounding particles.In the study of the influence of the topography on the particle flow motion and particle size sorting in the accumulation area,it was found that as the reverse slope angle of the accumulation area increases,the vertical particle size separation effect increases,and the vertical particle size separation effect weakens.Finally,two typical disaster cases are selected to calculate and analyze the disaster movements under different gradation conditions,and the calculation results are compared with the actual situation of the case.The calculated results are roughly consistentence with the actual disaster movement range.It shows that the discrete element method can better reduce geological hazards moving in the form of particle flow,and the calculation results also show unique particle size sorting characteristics.The study of particle flow motion and particle size sorting has practical significance for disaster prevention and management.