环形土壤磨损试验平台设计与试验

Design and Testing of Ring-shaped Soil Wear Test Platform

摘要:

现有土壤磨损试验中面临直线式土槽行程受限、圆形土槽受离心力和内外径速度差大、土壤整备困难等问题。基于此,研制了一种新型环形跑道式土壤磨损试验平台。该平台主要由环形土槽、闭环导轨和磨损测试装置 组成。磨损测试装置集成了驱动、姿态调节和土壤整备等功能模块,能够实现触土部件沿导轨的往复运动,复现多工况、长距离的触土部件土壤磨损试验。通过PLC控制运行速度(0~10km/h),同时可实现耕深、推土角及切土角 的精准调控。以1L-225 型梯形犁铧为测试对象,开展了140km的长距离磨损试验,并结合离散元法(DEM)构建了“土壤-犁铧”互作模型,从载荷、流场及表面形貌等方面验证了平台的可靠性。测试结果表明,测试平台入土深度波动偏差在±4.5mm以内,运行速度变异系数仅为2.1%,整备后的土壤坚实度达到了田间实测值的80%以上。可靠性验证表明,稳定耕作阶段的实测阻力与仿真结果的相对误差较低,且波动相位一致。土槽试验观测到的刃口点蚀、平行犁沟等磨损形貌及犁铧外表轮廓的演变规律与仿真结果高度契合。多工况试验验证了测试平台在复杂工况下的复现能力。该环形土壤磨损试验平台的运行参数可控、耕作载荷稳定,具备真实复现田间长距离耕作磨损失效的能力。

Abstract:

Existing soil wear testing methods face several limitations, including restricted travel distance in linear soil bins, significant centrifugal effects and velocity differences between inner and outer radii in circular soil bins, and difficulties in soil preparation. To address these issues, a novel annular track-type soil wear testing platform was developed. The platform mainly consisted of an annular soil bin, a closed-loop guide rail, and a wear testing apparatus. The wear testing apparatus integrated functional modules for driving, attitude adjustment, and soil preparation, enabling reciprocating motion of soil-engaging components along the guide rail and facilitating long-distance soil wear experiments under multiple operating conditions. The operating speed (0~10km/h) was regulated via a programmable logic controller (PLC), while tillage depth, rake angle, and cutting angle can be precisely adjusted. Using a 1L-225 trapezoidal ploughshare as the test specimen, a long-distance wear experiment covering 140 km was conducted. A discrete element method (DEM) model describing the soil-ploughshare interaction was also established to validate the reliability of the platform in terms of load characteristics, soil flow field, and surface morphology evolution. Experimental results indicated that the fluctuation of penetration depth remained within ±4.5mm, while the coefficient of variation of the operating speed was only 2.1%. In addition, the soil firmness after preparation reached more than 80% of the measured field value. Reliability verification demonstrated that the measured draft force during the stable tillage stage showed a low relative error compared with simulation results, with consistent fluctuation phases. Wear morphologies observed in the soil bin tests, such as edge pitting and parallel furrow patterns, as well as the evolution of the ploughshare outer contour, showed strong agreement with the simulation results. Multi-condition experiments further verified the platform’ s capability to reproduce complex operating conditions. The proposed annular soil wear testing platform provided controllable operating parameters and stable tillage loads, enabling realistic reproduction of long-distance field wear failure processes. It therefore offered significant value for research on drag reduction and wear resistance of soil-engaging components, as well as for service life prediction.