Design And Simulation Analysis On Rolled Broken Sleep Device For Alfalfa Seed

One of the main reasons for the dormancy of herbage seeds in alpine grassland is the seed coat obstruction.The dormancy rate of herbage seeds in alpine grassland and other small grain seed is higher,And the dormancy is usually broken by physical and chemical methods,traditional method of artificial friction and crushing is used to break seed dormancy in rural,nevertheless,the efficiency is low,At present,there are few researches on mechanical breaking techniques,and has such problems as the embryo and endosperm damage reduced the germination rate of seeds.This paper is based on the principle of roller compaction of traditional stone mill and the biomechanical characteristics of a kind of herbage seed,a kind of roller-crushing device is designed,and the effect of this design is verified by experiment.Based on the analysis of the motion and stress of the internal particles of the broken sleeping device based on EDEM,it is shown that the internal particles have a good uniform movement when the spindle speed is 96r/min.The experimental results show that when the spindle speed of this device is 96r/min,it is relatively good to break the sleep,and the rate of germination can reach 92~94%,the breakage rate is 3.2%,and the productivity is:(12~15)kg/h.It is very good to solve the problem of the low efficiency and the high rate of mechanical breaking.In order to explore the low loss mechanism of grass seed in alpine meadow,this paper provides some reference value for the development of low-loss sleeping equipment.The specific research contents of this paper include:(1)The composition,structure and mechanical analysis of stone mill.Analysis of the main structure and stone grinding to simplify construction stone grinding model,the analysis of the friction and wear principle and,further to the small grain seed force analysis of rolling action,from the Angle of sports kinetics of alfalfa seeds in the process of rolling force model.It provides a theoretical basis for the design of crushing parts for the broken sleeping device.(2)Study on the biological characteristics of forage seed in alpine meadow and its mechanical properties.In a typical alpine meadow grass seed-alfalfa as the research object,the determination of statistical alfalfa triaxial and grain size,and to test its mechanical properties,were determined the alfalfa and steel plate,aluminum sheet and plastic board between static and dynamic friction coefficient,contact area and contact materials as influence factors in the influence analysis,provide the beneficial reference for broken sleep device design.(3)Structural design of roller crushing device.In alfalfa biomechanics characteristic parameters as the basis,combining with stone grinding mechanics analysis and calculation,design of rolling device,the main working parts and other accessories are structure design,and using Solidworks software complete broken sleep device of the three-dimensional entity modeling;(4)Combining force of alfalfa seeds in the broken sleep,using EDEM discrete element software to create symmetrical dispersed particle model,alfalfa and simulating the actual simulation environment of broken sleep of alfalfa seeds at different positions in the broken sleep simulating the flow velocity,force analysis.(5)Verify broken sleep device performance,experimental results show that broken sleep device when the spindle speed of 96 r/min,broken sleep effect is good,broken sleep seed germination rate is 92 ~ 94%,seed breakage rate was 3.2%,the productivity is:(12 ~ 15)kg/h.