黏重土壤芯铧式播种开沟器优化设计与试验

Optimized Design and Testing of Core-share Seed Drill Furrow Opener Suitable for Heavy Clay

摘要:

针对播种开沟器在黏重土壤环境下作业时粘土严重、开沟阻力大等问题，本文设计了一种适宜黏重土壤的芯铧式播种开沟器。通过理论分析与经验设计，确定了芯铧式播种开沟器的结构参数为：入土角45°、入土隙角5°、斜切角30°、起始滑切角23°、终止滑切角45°、芯铧幅宽45mm。为进一步改善黏重土壤环境下芯铧式播种开沟器减粘脱附性能，基于仿生学的非光滑表面减粘降阻原理，采用增加凸筋方式对芯铧式播种开沟器犁体表面局部进行织构化改形设计，以凸筋几何参数为试验因素，利用EDEM软件模拟开沟器在土槽中的运动情况，采用响应面试验分析凸筋几何参数对土壤粘附量和开沟阻力的影响规律，优化凸筋几何参数最佳组合为：凸筋宽度7.623mm、凸筋高度1.344mm、相邻凸筋间距11.782mm，此时开沟器土壤粘附量为159.88g，开沟阻力为60.065N。土槽试验结果表明：在相同工作条件下，织构化改形开沟器较普通开沟器土壤减粘率为16.33%，开沟阻力降低了2.91%~4.45%，达到了预期的减粘降阻效果。

Abstract:

Aiming at the problems of serious clay and high resistance to furrow opening when the seeding coulter operates under the environment of clay soil, a core-share seeding coulter suitable for clay soil was optimally designed. Through theoretical analysis and empirical design, it was determined that the furrow coulter had an entry angle of 45°, a gap angle of 5°, a bevel angle of 30°, a start slip angle of 23°, a termination slip angle of 45°, and a with of 45mm. In order to improve the performance of the furrow opener in viscosity reduction and desludging, basing on the principle of viscosity and drag reduction of non-smooth surfaces of biomimicry, it was determined that the surface of the plough body of the furrow opener was locally textured reshaped by increasing the convex ribs, and the movement of the furrow coulter in the soil groove was simulated by EDEM software. Using EDEM software to simulate the movement of the furrower in the soil groove, taking the surface characteristic geometric parameters as the test factors, the soil adhesion amount and furrowing resistance as the evaluation indexes, and adopting the response surface test to analyze the influence law of each geometric parameter on the evaluation indexes, it was determined that the optimal combination of the surface characteristic geometric parameters of the furrower body was as follows: width of the convex rib was 7.623mm, thickness of the convex rib was 1.344mm, and the spacing between the adjacent convex ribs was 11.782mm, at this time, the soil adhesion amount of the furrower was 159.88g, the furrowing resistance was 60.065N. The soil trench test showed that under the same working conditions, the soil viscosity reduction rate of the textured reshaping furrow opener was 16.33%, compared with the conventional furrow coulter, the working resistance was reduced by 2.91%~4.45%, achieving the expected viscosity reduction and resistance effect.