基于离散元法的施肥机钻头性能特性优化研究OA

To optimize the structural parameters and operational performance of the fertilizer applicator drill bit,a soil particle flow model was constructed based on the discrete element method.Dynamic simulation of the drill bit penetration and cutting process was conducted using EDEM software,and response surface experiments were designed via Design-Expert.The cutting edge angle,helical airfoil lift angle and rotational speed were taken as input variables,and the cutting resistance torque was as the response value.A regression model was established and subjected to analysis of variance.The results showed that the overall regression model was significant,and the rotational speed exerted a significant effect on cutting resistance torque.The optimal parameter combination was obtained as:cutting edge angle of 36.45°,helical airfoil lift angle of 25.14° and rotational speed of 160.364 r·min−1.Under these condition,the regression model predicted a cutting resistance torque was 3.51 N·m,while the discrete element verification yielded 3.45 N·m,with a relative error of 1.74%.On this basis,lightweight design of the drill bit was performed using the ANSYS platform,reducing the bit mass by 24.54%.The maximum equivalent stress increased from 58.681 MPa to 70.417 MPa,and the maximum total deformation increased from 0.024 598 mm to 0.029 518 mm,both remaining within the allowable ranges for material strength and engineering deformation.Modal analysis indicated that the first six natural frequencies of the optimized drill bit were significantly higher than the motor excitation frequency,indicating low resonance risk.Above results could serve as reference for the structural parameter optimization and lightweight design of digging mechanisms in fertilizer applicators.