植树机挖坑机构螺旋式钻头性能特性优化研究OA北大核心

In order to achieve low energy consumption and lightweight simplification of the excavation mechanism for planting machine,this article carried out structural design and parameter optimization for the drill bit.The discrete element method was applied to construct soil model,while the dynamics of the drilling process was simulated by EDEM software.Design-expert software was used to design the response surface method test scheme.Taking the cutting edge angle,helical airfoil lift angle and rotational speed as independent variables,and the resistance moment of drill bit as response value,the regression equation of resistance moment was constructed and the variance analysis was performed.The optimal parameter combination was obtained as follows:cutting edge angle of 32.778°,helical airfoil lift angle of 28.316°,drill bit rotational speed of 160.346 r·min-1,and under the above parameter combination the resistance moment was 275.137 N·m,with verification error of only 4.38%.Optimization of the drill bit parameters was conducted by ANSYS,and the results showed that there was a 34.39%reduction in weight after optimization.the stress increased by 76.28%with a safety factor of 2.61;the deformation increased by 59.79%which still was below 1 mm.Modal analysis was also carried out on the drill bit after optimization,and the various orders of inherent frequency avoided the main excitation frequency,preventing resonance from occurring.These research results provided references for parameter optimization of the excavation mechanism.