仿魁蚶表面肋-槽结构的水田打浆机刀片耐磨设计与试验

Design and Experiment on Wear Resistance of Paddy Field Pulping Machine Blade Inspired by Rib-Groove Structure of Scapharca broughtonii

摘要:

水田打浆机刀片在泥浆环境中作业时,承受土壤颗粒的摩擦、冲击和冲蚀作用,易出现磨损严重、使用寿命短等问题。本文选取具有优异耐磨损特性的潮间带魁蚶壳体表面微观结构为仿生原型,开展打浆机刀片仿生耐磨设计与试验研究。利用超景深显微镜提取魁蚶壳体表面肋槽结构特征,分析表面流场和颗粒运动轨迹,揭示其耐磨机理。基于离散元法(EDEM)建立“刀片泥壤”互作模型,分析肋槽结构参数变化对法向和切向接触能量的影响 规律,采用Box-Behnken 响应面法(RSM),对凹槽深度、宽度及放射肋宽度进行多目标参数优化。仿真结果表明: 当凹槽深度为0.27mm、凹槽宽度为0.68mm、放射肋宽度为0.18mm 时,仿生刀片的法向累计接触能量(1.406J) 与切向累计接触能量(0.85J)最小。基于参数优化结果试制仿生刀片并进行田间对比试验,结果显示:优化后仿生刀片的磨损质量和磨损率分别为2.048g和0.383% ,与普通光滑刀片相比,磨损率降低了65.53%。可为水田机械触土部件的耐磨研究提供理论依据。

Abstract:

When paddy field pulping machine blades operate in a muddy environment, they are subjected to friction, impact, and erosion by soil particles, which easily lead to severe wear and a short service life. The microstructures on the shell surface of intertidal Scapharca broughtonii—possessing excellent wear resistance—were selected as the bionic prototype to carry out design and experimental research on the bionic wear resistance of pulping machine blades. The “ rib-groove” structural features of the Scapharca broughtonii shell surface were investigated by using a 3D microscope, and the surface flow field and particle movement trajectories were analyzed to reveal the wear resistance mechanism. Based on the discrete element method (EDEM), a “blade-soil” interaction model was established to analyze the influence of “rib-groove” structural parameter variations on normal and tangential contact energy. The Box-Behnken response surface method (RSM) was adopted for multi-objective parameter optimization of groove depth, groove width, and rib width. The simulation results showed that when the groove depth was 0.27 mm, the groove width was 0.68mm, and the rib width was 0.18mm, the normal cumulative contact energy (1.406J) and tangential cumulative contact energy (0.85J) of the bionic blade were minimized. Bionic blades were prepared based on the optimized parameters, and field comparative tests were conducted. The results indicated that the wear mass and wear rate of the optimized bionic blade were 2.048g and 0.383% , respectively. Compared with conventional smooth blades, the wear rate was reduced by 65.53% . The research result can provide a theoretical basis for the wear resistance research of soil-contacting components in paddy field machinery.