中文摘要：

优化铧式犁犁体曲面形状,降低耕作阻力,是一项亟待解决的问题。从犁体曲面成型方法可知,导曲线形状是影响铧式犁耕作阻力的一个重要因素。为此,以BTU35犁体为基础,在Solid Works中建立5种不同导曲线犁体,并将模型导入ANSYS进行显示动力学分析,得到其耕作阻力。仿真试验表明：以四次多项式曲线为导曲线形成的犁体耕作阻力较小,在3km/h时降阻3.75%,7km/h时降阻4.56%,平均降阻3.93%。结合不同导曲线曲率半径变化情况与工作阻力之间的关系,可得结论：导曲线曲率半径变化复杂的犁体有较好的减阻性能。

英文摘要：

Optimizing the plow＇ s geometric shape to reduce working resistance is an urgent problem to be solved. The di- rectrix shape has an important effect on working resistance according to molding principle. Research on the basis of BTU35 ,five kinds of plows were set up with five types of directrixes in solidworks. At last, the plows were imported into ANSYS software. Working resistances were obtained when some explicit dynamics analysis had been finished. Simulation experiments that the plow formed by quartic polynomial directrix has better drag reduction performance. The plow reduced working resistance by 3.75 percents in 3km/h,4.56 percents in 7km/h, 3.93 percents on all speed range. Considering the relationship between curvature radius of directrixes and working resistances, we can draw a conclusion that the plow formed by directrix with complex curvature radius has better drag reduction performance.