Abstract:

In order to meet the requirements of mechanical planting of white radish and solve the problem of lack of related planting machinery in southwest China， an air-suction precision seeder was designed. Through calculation and theoretical analysis， the key structural parameters of the seeder were designed. The force of seeds in the filling， carrying and seeding stages were analyzed， and the main factors affecting the sowing performance were determined. By using Fluent software， the influence of different hole size parameters on the air flow of the negative air pressure chamber was simulated， and the optimal hole diameter parameters were determined， the diameter of the hole was 2.079~2.178 mm. Through parameter optimization， the best parameter combination was obtained： the diameter of the seed plate was 200 mm， the distribution of the hole diameter was 160 mm， the number of holes was 16， and the hole diameter was 2.2 mm. The results of the bench test of seeding performance showed that the working speed was 30.54 r·min^-1， the air pressure in the negative air pressure chamber was 6.58 kPa， the single grain qualification index of the seeder was 95.61%， the missed seeding index was 0.64%， and the reseeding index was 2.04%. The results improved the performance of the seeder and provided reference the design and manufacture of white radish precision seeding machine.

Key words: white radish, air suction seed metering device, precision sowing, simulation

摘要：

为满足白萝卜机械种植要求，解决我国西南地区缺乏相关种植机械问题，设计了一种气吸式精量排种器。通过计算与理论分析，设计了排种器关键结构参数；对充种、携种和投种阶段种子受力进行分析，确定了影响播种性能的主要因素。利用Fluent软件仿真模拟不同型孔尺寸参数对负气压室气流影响，确定了最佳型孔直径参数，其型孔直径范围为2.079~2.178 mm。通过参数优化得到最佳参数组合为：排种盘直径200 mm、型孔分布直径160 mm、型孔个数16个、型孔直径2.2 mm。排种性能台架试验结果表明，在工作转速为30.54 r·min^-1，负气压室气压为6.58 kPa，排种器单粒合格指数95.61%，漏播指数为0.64%，重播指数为2.04%。该研究结果有助于提高播种器性能，为白萝卜精量播种机器设计与制造提供可靠参考。

关键词: 白萝卜, 气吸式排种器, 精量播种, 仿真