三七收获机挖掘铲减阻特性分析与试验OA北大核心CSTPCD

Aiming at the problems of high resistance and high injury rate in mechanized harvesting of Panax notoginseng in hilly and mountainous areas,taking different shovel types of excavator as the research object,comparative experimental research on the operation mechanism and parameter optimization of excavator shovel of Panax notoginseng harvester was carried out.Through theoretical analysis and mechanical calculation,the main structural parameters of each shovel type excavator were determined,and the three-dimensional model of the excavator was established by Solidworks.The simulation and comparison tests of displacement and flow direction of four shovel types of excavator were carried out to track the spatial motion trajectory of rhizome particles and soil particles,and the triaxial displacement segments were obtained.It was showed that the special curvature change of the bionic curve of the boar head had a significant impact on the soil breaking resistance,and the bionic shovel surface reduced the excavation resistance by changing the flow direction of soil particles.By using the Design-Expert 13 software,taking the shovel length,width and blade inclination as the test factors,and taking the excavation resistance as the test index,the combination test was carried out.The optimal combination of operation parameters was obtained as the shovel length of 354 mm,the shovel width of 40 mm,and the blade inclination of 70°.Under this combination,the average excavation resistance was 439.75 N.The high-speed photography experiment was carried out to obtain the movement trajectory of Panax notoginseng rhizome and soil.The results showed that the movement trend of Panax notoginseng rhizome and soil particles was consistent with the simulation experiment,which verified the reliability of the discrete element model.The orthogonal test was conducted with the penetration angle,blade spacing and excavation speed as the test factors and the excavation resistance as the test index.The results showed that the primary and secondary order of the influence of different working parameters on the excavation resistance was the penetration angle,blade spacing and excavation speed.The optimal combination of working parameters was the penetration angle of 15°,blade spacing of 80 mm and excavation speed of 0.4 m/s.Through comprehensive evaluation of the performance of reducing viscosity and resistance,the bionic excavator had the best operation effect.