Analysis Of Motion Law Of Buckwheat Rice And Optimization Of Sieving Performance Parameters

It is of great significance to explore the motion rules of the materials on the vibrating screen of buckwheat rice sieve,and to optimize the parameters of the screening equipment,and then to improve the effect of buckwheat rice screening,at the same time,in order to make the study about influence factors of buckwheat rice sieving effect of more comprehensive,in this paper,using discrete element method to carry out the effect of screen sieve amplitude on buckwheat rice screening.The study determines the amplitude of the screen sieve when the angle between dynamic and fixed eccentric block of the vibration motor is 0°~60°,and measures the basic contact parameters of buckwheat and buckwheat rice,using discrete element software EDEM to calibrate that parameters;The study also uses discrete element software EDEM to simulate the screening process of buckwheat rice for different amplitude of the screen sieve and analyzes the effect of screen sieve amplitude on the motion of buckwheat rice on sieve and its distribution under sieve based on simulation result;Besides,the study chooses the buckwheat with a diameter range of 4.6mm~4.8mm as the test material and selects the error-sifting rate and the undivided rate as the test index to carry out the single factor test of the effect of screen sieve amplitude on buckwheat rice screening effect.The result shows that the control interval of the angle between dynamic and fixed eccentric block of the vibration motor is 10°,the adjusting range of screen sieve amplitude is that the X direction is 2.08mm~1.76 mm,the Y direction is 0.06mm~0.15 mm,the Z direction is 2.72mm~2.34 mm.The error between the measured value and the simulation calibration value of the basic contact parameter is less than 7.9%.With the increase of the angle between dynamic and fixed eccentric block of the vibration motor,the error-sifting rate first decreases and then increases,the undivided rate first increases and then decreases.When the angle between dynamic and fixed eccentric block of the vibration motor is 10°,minimum error-sifting rate is 2.28‰,the undivided rate is 15.12‰,at this time,the screen sieve amplitude is 2.06 mm in X direction,0.14 mm in Y direction and 2.71 mm in Z direction.The result of discrete element simulation shows that buckwheat and buckwheat rice are all leaping forward,and the jumping height and distance are not uniform;the smaller the amplitude of the screen sieve,the smaller the rear movement speed of the buckwheat rice and the higher the distribution,besides,the number of buckwheat rice is decreased.The law of buckwheat rice movement obtained by discrete element simulation is consistent with theoretical analysis,the number and distribution of buckwheat rice under sieve are the same as those of the experiment,these all illustrated that using discrete element method to study buckwheat rice sieving is feasible.