Authors

Abstract

In order to explore the effect of vibration on the adsorption characteristics of small particle size seeds, based on the discrete element method, the changes in the variance of the average tangential force of seeds under different amplitudes were analyzed. The variance of the average tangential force of the seeds increases exponentially with the amplitude. It is inferred that the vibration will change the intensity of the population disturbance. This reduces the seed transient tangential force i.e. transient seed internal friction. To improve the adsorption characteristics of small-sized seeds, the adsorption characteristics at different amplitudes were verified with bench tests. Increasing the amplitude can improve the adsorption characteristics of small-sized seeds. To determine the optimal operating parameters, based on the Box–Behnken test principle, response surface tests were carried out using rotational speed, negative pressure, and amplitude as test factors and seed suction compliance and leakage rate as evaluation indexes. The optimum operating parameters were determined as: rotational speed of 12.05 r/min, negative pressure of 0.89 kPa, and amplitude of 5.75 mm. At this time, the seed suction pass rate was 95.1% and the leakage rate was 2.1%. which is in line with the standard requirements.

Abstract in Chinese

为探究小粒径种子振动吸附特性，基于离散元法，以气吸式藜麦排种器为模型，利用EDEM软件进行仿真试验，分析不同振幅下种子平均切向力方差的变化，种子平均切向力方差随振幅呈指数增加，据此推断振动会改变种群扰动强度，从而降低种子瞬态切向力即瞬时种子内摩擦力，以此提高种子吸附特性；通过台架试验验证不同振幅下的吸附特性，验证结果与仿真分析结果一致，增大振幅可改善吸种特性。基于 Box-Behnken试验原理，以转速、负压和振幅为试验因素，以吸种合格率和漏吸率为评价指标，进行了响应面试验，得到各因素对指标影响关系，利用多目标优化方法确定较优工作参数组合，当转速为12.05 r/min，负压为0.89 kPa，振幅为5.75 mm时，吸种合格率为95.1%，漏吸率为2.1%，符合标准要求。