Design Of Self-Service Rice Mill And Discrete Element Analysis Of Milling Mechanism

With the continuous improvement of our country’s living standards,people have higher and higher requirements for the quality of food.As the most important food in our country,rice is of great significance to the study of its processing process.How to eat fresh and nutritious rice and how to reduce the rate of broken rice have become hot issues in the agricultural field.The purpose of this article is to design a low-breaking rate of "milled now for sale" self-service rice milling machine to provide the people with high-quality rice.The work and research results of this article include:(1)Through market,social surveys and literature review,we can understand the market demand of self-service rice milling machines with "crush now and sell now".Determined the function of the rice mill and carried out modular analysis of the function.Besides,determine the composition of the overall structure,design the logical control relationship and system control scheme of each functional structure.(2)Based on the discrete element numerical simulation to model the core rice milling structure,and analyze its milling mechanism,it is proposed that milling uniformity is the main reason that affects the rate of broken rice.The EDEM software was used to simulate the rice mill,and the influence of the height of the rib on the main shaft of the roller on the milling was analyzed.The simulation results show that the height of the spiral rib with the best axial movement consistency is 8mm,the height of the rib with the best radial movement consistency is 4mm,and the height of the rib with the best circumferential movement consistency is 5mm.The periodic fluctuation of the grinding force gradually decreases with the height of the ribs,and tends to be stable after the height of the ribs is greater than 4mm.(3)Using the bonding ball model to simulate the grinding and crushing effect of rice grains in the rice grinding room.The total normal force is obviously positively correlated with the bonding bond fracture rate,and a comparison index that controls the degree of grinding is consistent.Simulate and analyze the density of different rice milling chambers.Obtained that when the grinding degree index is consistent,the particle density per unit axial distance is 18.54 grains per millimeter,the broken rice rate is the lowest.(4)The self-service rice mill was successfully built and debugged,The reliability of the kinematic simulation and the reliability of the rice broken rate simulation analysis of the rice mill were verified by experiments.The experimental results show that the kinematic characteristics of the rice mill simulation model constructed in this paper are basically consistent with the experiment.The trend of broken rice rate with outlet pressure obtained by simulation is basically consistent with the experiment.