Research And Measurement Device Design Of Bulk Material Penetration Resistance

The study of bulk materials has received more and more attention at home and abroad.Research on the penetration characteristics of grain particles such as rice can help people to understand the internal structure and contact properties of granular particles,facilitate the storage and transportation of rice,and rational use,for example,on a large scale.Grain intake and grain ventilation also have implications.The same soil also belongs to a kind of loose granules,and the study of the intrinsic characteristics of the soil is of great significance in guiding agricultural production.The extensive use of agricultural machinery has led to increasing soil compaction and has had a negative impact on the sustainable development of agriculture.At present,the degree of soil solidity is generally reflected by measuring soil penetration resistance at home and abroad.There are many factors affecting penetration resistance.This paper mainly studies the influence and law of cone penetration velocity,depth and moisture content on soil penetration resistance under high-speed motion.By measuring the soil penetration resistance,we can realize the judgment of soil compactness,help us to judge the farming time and improve the basis for the behavior of the loose soil,which is of great significance for achieving sustainable agricultural development.This article intends to study the bulk material penetration resistance characteristics by the following five parts.(1)In-depth study of domestic and foreign research status,familiar with the current domestic and foreign research results and progress on the resistance to penetration of bulk materials,and summarize the advantages and disadvantages of these studies.A large amount of literature was consulted in the previous period,and it was found that at present,mainly in China,simulation studies are used to conduct theoretical research and less research is conducted through actual experiments.The foreign scholars studied the soil penetration resistance earlier and studied more.Although some theoretical formulas were obtained,they were not closely related to the tests and lacked the penetration of speed,depth,and moisture content for high speed sports.The influence of resistance.Therefore,this paper attempts to study the relationship between penetration resistance and penetration velocity through theoretical analysis.At the same time,the relationship between penetration resistance and penetration depth and moisture content is experimentally studied.(2)Test analysis,through experiments to explore the impact of penetration speed,penetration depth and moisture content on rice and soil penetration resistance.The test results show that the penetration resistance increases with the penetration velocity at the same depth,and the penetration resistance increases with the depth at the same velocity.The empirical formula can be better.Explain the relationship between resistance and speed in rice penetration.The higher the soil moisture content,the smaller the penetration resistance and the decreasing trend is smaller and smaller.(3)Theoretical analysis,through the previous experience formula,combined with the existing theory,the theoretical analysis of the cone penetration process.(4)Simulation study,using a contact model,simulation of 0.2 m / s ~ 3.0 m / s uniform penetration of simulation materials,further study of penetration resistance and penetration velocity and depth relationship.Another contact model was chosen to simulate soil penetration tests with different moisture contents.The simulated particles were generated using spherical particles as the basic model.The simulation results showed less fluctuation than the experimental results.(5)According to ASAE conical standards,a soil penetration resistance measurement device based on transient acceleration detection was designed through the need for tests and actual agricultural production.The device is simple in structure,easy to carry,and easier to install and remove.Meet the need for soil penetration resistance measurement under high-speed motion.Studies have shown that under high-speed motion,the penetration resistance increases with increasing penetration speed;at the same speed,resistance increases with depth.Transient acceleration detection is more accurate than high-speed camera measurement methods.The relationship between penetration speed,depth and resistance can be represented by a threedimensional curve.The fitting coefficients are all greater than 0.90.Under the same conditions,the penetration resistance of rice is less than the soil penetration resistance,and the soil penetration resistance is more volatile than rice.The theoretical formula can better characterize the relationship between rice penetration resistance and penetration speed.The greater the moisture content,the greater the resistance.The relationship between water content and penetration resistance can be represented by a logarithmic curve with a fitting coefficient of 0.988.