空载状态下往复式棉秆切割器动力学仿真与试验

Simulation and experiment of reciprocating cutter dynamics of cotton stalk under no-load

为了能够迅速、可靠地确定空载状态下往复式棉秆切割器的切割阻力和功耗等数据从而优化其设计,选择一种以偏置式曲柄连杆机构驱动的往复式棉秆切割器作为仿真与试验研究对象。采用SolidWorks进行了虚拟样机设计,利用ADAMS对空载状态下往复式棉秆切割器进行了动力学仿真研究,依据仿真数据应用响应面方法对切割峰值阻力与机架所受振动力进行了试验分析,确定了割刀平均切割速度为0.8m/s、配重块质量为1.5kg、安装位置滞后于曲柄位置170°时切割峰值阻力与机架所受振动力最小,分别为450和380N。利用研制的往复式棉秆切割试验台,对空载状态下的切割阻力随着割刀平均切割速度的变化进行了试验研究,并与仿真数据进行了对比分析。结果表明,切割峰值阻力的实测值与模拟值相对误差为7%,机架所受振动力的实测值与模拟值相对误差为7.7%,仿真数据可靠,能替代试验数据作为参考依据,为低功耗棉秆切割收获装备的研发提供了一种设计参考。

In order to quickly and reliably measure the cutting resistance and power dissipation of the cutter under no-load, a reciprocating cutter of cotton stalk was taken as an object of simulation and experiment. It was driven by deflection crank-connecting rod mechanism, its virtual prototype was designed by Solid Works and dynamic simulation was studied under no-load using ADAMS. An experimental analysis of cutting peak resistance and vibrating force on frame was made using response surface methodology based on simulation data. Results showed that the cutting peak resistance and vibrating force on frame was the minimum when average cutting speed of cutter knife was 0.8 m/s, clump weight was 1.5 kg, and set on 170~ lagging behind crank position. The minimum values were 450 and 380 N. The experimental researches on changes of the cutting resistance with the average cutter cutting speed under no-load were made on the developed reciprocating cotton cutting test-bed, their results were compared with simulation data. Results showed that the relative error of cutting peak resistance and vibrating force on frame between the simulation and experimental data was 7% and 7.7%, respectively. The simulation result was reliable and could be regarded as a reference for restituting the experimental data. This research provides a design reference for development of low power consumption cutting harvesting equipment.