| Panax notoginseng belong to the genus panax ginseng of Araliaceae,it is a kind of rare Chinese herbal medicine in southwest China,has great medicinal and economic value.In recent years,with the increasing market demand,planting area of Panax notoginseng in Yunnan province growth rapidly,however,Panax notoginseng harvest is still using artificial digging with low efficiency and tremendously labor intensive.Relevant personnel developed a series of root harvesting machinery aimed at Panax notoginseng planting patterns and agronomic requirements.Some achievements have been made,but some key technologies and equipment of Panax notoginseng mechanized harvesting still need to be further improved.In this study,on the basis of the previous studies,the mining system,elevator system and root soil separation system were optimized and improved according to the requirements of the Panax notoginseng planting.A kind of Panax notoginseng harvest experiment platform is developed,which is composed of Panax notoginseng excavation,transportation and soil removal,and bench test and field test were carried out.This study was based on the research and development key new product development project of Panax notoginseng production mechanization key equipment of Yunnan province,the research contents and the conclusions are as follows:(1)The main object of study used Wenshan Panax notoginseng in Yunnan province,at the same time,did field research in Shilin.Mile and other Panax notoginseng planting areas.Learn about the latest agronomic requirements.In this paper,the mechanical properties of Panax notoginseng root tubers and the physical and mechanical properties of the soil were studied,and the overall structure of the Panax notoginseng harvest test platform was determined.(2)In view of the problems existing in the Panax notoginseng harvesting machines,a reasonable solution is proposed to determine the overall structure of the Panax notoginseng harvest test platform.In the premise of not reducing the Panax notoginseng harvest rate,reduce the degree of hilling machine,design a kind of combined mining shovel,improved lifting chain,choosing vibration wheel,improving reliability and transportation device.(3)The EDEM software was used to analyze the Panax notoginseng excavation process by discrete element method,through comparison with the simulation of common digging shovel resistance,it is proved that the resistance of the combined digging shovel is better than that of the traditional digging shovel at the working speed of 0.5m/s,0.7m/s,0.9m/s,and digging depth of 100mm,150mm and 200mm.Explained the ability of combination shovel to reduce the digging resistance.The simulation results show that the particle trajectory of the soil around the combined shovel,which proves that there is still a high harvest rate under the premise of drag reduction.(4)Considering Panax notoginseng root and the soil attached on the top as a type of root soil complex,established the simulation model of Panax notoginseng soil complex,and the dynamic simulation software ANSYS/EXPLICIT was used to simulate the rolling process,The simulation results showed that on the process of extrusion and shearing failure of Panax notoginseng root soil complex under the grinding roller and the supporting plate with holes,with the rotation of the roller,the soil deformation and failure in the positive direction and the reverse direction,in which the ground breaking is the most obvious.The soil contacted by the roller is crushed and broken,and the stress value of the soil in contact with the roller is the largest,soil fracture and fragmentation.(5)A field experiment was carried out on the Panax notoginseng harvesting rate of a digging and a lifting device as a prototype,and a regression model was established based on the response of the Panax notoginseng harvesting rate,analysis of the sequence of the factors affecting the harvest rate is buried gap angle,blade angle,speed of operation.Through the factors has significant effect on interaction model,doing response surface analysis,obtained the results of the blade angle and ground clearance angle changes of the harvesting rate.The optimum operating parameters were obtained by using the optimized model:the shovel face angle was 20°,the clearance angle was 12°.and the operating speed was 0.75m/s.The yield of field test was 98.38%,which was similar to the result of model optimization,close to model optimization results,meet job requirements.At the same time,the average injury rate of prototype Panax notoginseng was 3.6%,the operation efficiency reaches 0.3 hm2/h.and the main technical indexes all have met the requirements.(6)Using Panax notoginseng root soil composite as samples,the free fall motion provides the initial velocity of the sample,with two sets of orthogonal design,discuss the optimal combination of the first and second grade level rolling compaction in soil with Panax notoginseng to the rate of response respectively.The results showed that the surface shape of the two rollers is square convex,the rolling gap of the roller and the hole plate is 23mm.the first roller speed is 200r/min,The optimal working scheme of the whole root soil separation device when the rotating speed of the second rollers is 100r/min.The primary and secondary order of each factor in the first and the second rolling orthogonal experiments are as follows:Rolling clearance→Roller surface shape→Rolling speed. |
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