悬挂式水田单侧修筑埂机数值模拟分析与性能优化

为提高水田机械田埂修筑质量,探索各工作参数对悬挂式水田单侧修筑埂机作业性能的影响,依据离散元法建立机械部件-土壤间作用模型,运用EDEM软件对机具旋耕切削集土和镇压筑埂成型阶段进行仿真分析,研究机具作业质量和功耗的动态变化规律,分析影响筑埂性能的主要因素。结合正交试验设计和数值模拟技术,以机具前进速度、旋耕工作转速和旋耕入土深度为试验因素,田埂坚实度和作业功耗为试验指标,采用多目标变量优化方法建立因素与指标间数学模型,运用Design-Expert 6.0.10软件进行数据处理优化。结果表明,影响机具综合作业性能的主次因素为机具前进速度、旋耕入土深度、旋耕工作转速;当机具前进速度、旋耕工作转速和旋耕入土深度分别为0.3 m/s、470 r/min和200 mm时,机具作业性能较理想,田埂坚实度和作业功耗分别为1 890.0 kPa和30.07 kW,其功耗较优化前降低9.93 kW。经土槽台架试验验证,台架试验结果与仿真优化结果基本一致,田埂坚实度和作业功耗相对误差分别为4.26%和5.11%,满足水田修筑埂农艺要求。

Numerical Analysis and Performance Optimization Experiment on Hanging Unilateral Ridger for Paddy Field

Paddy field mechanization ridging is constructed by agricultural machinery to meet the production requirements of rice irrigation and ridge technology. It can improve the yield of grain crops and reduce the waste of water resources, which is conducive to the construction of standardized farmland in China. In order to improve the quality of paddy field mechanization ridging and investigate the working parameters of performance of hanging unilateral ridger, the interaction model of machinery and soil was established by using distinct element method. The EDEM software was employed to simulate the processes of rotary tillage collecting soil and compacting ridging. And then the dynamic behaviors of performance and power consumption of ridger were researched under the working conditions. The principal factors which affected the quality of machine operation were analyzed. Orthogonal simulation experiment was carried out with forward speed, rotational speed, tillage depth as experimental factors and ridge density and power consumption as assessment consumption. Based on experimental data, a mathematical model was built by using the Design-Expert 6.0.10 software, and the experimental factors were optimized, the best combination was achieved. By using range analysis method and variance analysis method to determine the importance index, the primary and secondary indexes were as follows: forward speed, tillage depth and rotational speed. And the experiment results showed that forward speed was 0.3m/s, rotational speed was 470r/min, tillage depth was 200mm, and the maximum ridge density was 1890.0kPa, the minimum power consumption was 30.07kW, and the improved power consumption exceeded the original one by 9.93kW. Finally, the bench test was conducted to verify the accuracy of simulation results and optional parameters, which showed that the relative error of ridge density was 4.26% and the relative error of power consumption was 5.11%, indicating that the simulated values were basically coincided with testing values, which proved that the modeling and simulating methods adopted met the content requirement.