保护性耕作拟合曲线型深松铲设计与试验

针对东北地区深松整地作业中,深松铲土壤扰动量和耕作阻力大的问题,以离散元(EDEM)软件仿真分析铲尖对土壤的作用为依据,设计了拟合曲线型深松铲。采用离散元软件模拟深松铲铲尖在土壤中的运动,获得铲尖上方土壤颗粒运动轨迹的拟合曲线和拟合方程,采用线元设计法对线形优化,获得铲柄外形曲线;同时设计了刃部、切削刃角、入土角,并通过铲柄与铲尖的互作效应试验验证了分层的可行性与合理性。土槽对比试验表明,拟合曲线型深松铲有效降低了土壤扰动量和耕作阻力,比折线式深松铲土壤扰动量减少了53.6%,耕作阻力减少了36.23%;比圆弧式深松铲土壤扰动量减少了66.18%,耕作阻力减少了29.18%。田间对比试验表明,拟合曲线型深松铲比折线式深松铲回土面积增加了81.03%,比圆弧式深松铲的回土面积增加了146.95%。土槽和田间试验表明,拟合曲线型深松铲土壤扰动量小、耕作阻力小,满足深松作业的要求。

Design and Experiment of Fitting Curve Subsoiler of Conservation Tillage

A fitting curve subsoiler was designed aiming at the problems of large soil disturbance and large tillage resistance caused by subsoiler in sub-soiling site preparation work in Northeast China. The discrete element (EDEM) software was used to simulate the movement of the tip of a subsoiler in the soil. Through calculating, the fitting curve and fitting equation were obtained from the trajectory of soil particles above the tip of shovel. After summarizing, the method of line element design was used to optimize the alignment to acquire the curve of shovel handle shape, meanwhile, to design the edge, lip and penetration angle were cut. Then the interaction effect test of shovel handle and shovel tip were used to prove the feasibility and rationality of the design. The contrast test of soil trough showed a fitting curve subsoiler can effectively reduce the soil disturbance and tillage resistance. Compared with polygonal subsoiler, the fitting curve subsoiler made the soil disturbance reduced by 53.6%, tillage resistance reduced by 36.23%. Compared with circular subsoiler, it made the soil disturbance reduced by 66.18% and the tillage resistance reduced by 29.18%. Compared the fitting curve subsoiler with the polygonal subsoiler with field experiment, it was showed that using the fitting curve subsoiler made the soil return area increased by 81.03%. Compared with circular subsoiler, the fitting curve subsoiler made the soil return area increased by 146.95%. Both the soil trough experiment and the field experiment verified that the fitting curve subsoiler can make the soil disturbance smaller and tillage resistance smaller, which met the requirements of sub-soiling operation.