番茄藤秸秆高效切割的机理及仿真研究

番茄是我国重要的蔬菜作物之一,其大面积种植带来了严重的秸秆处理问题。由于番茄藤秸秆根部表皮较厚,有较多的维管束,具有较强的抵抗外载荷的能力,不易切断,其切割方式、切割刀片及切割参数等对切割性能都具有重要影响。通过对番茄藤秸秆专用切割刀片切割力学分析和切割力计算分析研究了番茄藤秸秆高效切割的机理。建立了番茄藤秸秆高效切割模拟模型,运用仿真技术对番茄藤秸秆切割过程进行了有限元分析;对不同结构参数切割刀片进行切割对比试验。结果表明:1切割力随着秸秆横截面积的增加,随着刀片楔角的增加而逐渐增大,随着刀片后角的增加呈下降的趋势;2随着切割速度的增加,刀片切割应力有一定的增大,切割能量损耗加大,仿真分析得到的最大切割应力和理论计算结果在数值上较接近,证明了所推导的刀片切割力计算方法的正确性,验证了秸秆切割模型的合理性;3专用等滑切角(40°)锯齿型刀片与等滑切角平型刀片和普通刀片相比,2 kg的番茄藤切割电能最小,为0.18k W·h,切割时间最短,为2min,切割效率最高,切割后粗细均匀,效果也最好。该研究揭示了采用等滑切角锯齿型刀片对番茄藤秸秆高效切割机理和性能,为研制番茄藤秸秆专用切割机及实现高效切割提供了理论和试验依据。

Mechanism and Simulation Analysis of Efficient Cutting for Tomato Straw

This paper studied the efficient cutting mechanism of tomato straw by cutting force analysis and cutting force calculation of special cutting blade for tomato straw.Also, efficient cutting simulation model of tomato straw is established and applied to the finite element simulation analysis for the tomato straw cutting process.And it finished the cutting contrast experiments for different structure parameters of cutting blade.The results showed that: (1) The cutting force gradually increases with the increase of straw cross-sectional area and blade's wedge angle, and decreases with the increase of blade's back angle.(2) With the increase of cutting speed, the blade's cutting stress also increases as well as the cutting energy loss increases.The theoretical calculation of the maximum cutting stress is relatively closed with the simulation analysis results in value, which proves the correctness of the calculation method of blade cutting force theory derived in front, and verifies the rationality of straw cutting simulation model.(3) Compared with the ordinary blade and equal sliding-cutting angle flat blade, the cutting power of 2kg tomato vines cutting by the special equal sliding-cutting angle(40°) saw teeth type blades is the minimum which is 0.18 kw·h, the cutting time is 2min which is the shortest, the cutting efficiency is the highest, the cutting effect is the best, and the straw debris are uniform thickness after cutting.