气吸滚筒式棉花精密排种器流场分析

为分析气吸滚筒式精密排种器充种性能的影响因素和负压腔流场分布规律,建立了充种过程种子在气流场中的力学模型,利用Gambit软件建立滚筒负压腔仿真简化模型,运用Fluent软件对影响充种性能的吸孔形状、吸孔直径及滚筒负压腔流场分布进行了数值模拟。采用正交试验的方法设计试验方案,研究滚筒转速、吸孔直径及气室负压对排种性能指标的影响,结果表明:滚筒转速为12r/min、吸孔直径为3.5mm、气室负压为4.8k Pa时,排种效果最佳,合格指数为9 3%,漏播指数为2%,重播指数为5%,满足棉花种植农艺要求。

Airflow Field of Pneumatic Cylinder Array Precision Seed-metering Device for Cotton

In order to study the factors on seed suction performance of the pneumatic cylinder array precision seed-metering device for cotton and airflow in cylinder cavities of the cylinder seed-metering device. The working principle and component of precision seeder were introduced, and the mechanical model of single cotton seed during the air-suction filling process was established in this paper. Simplified model of air flow channel in cylinder cavities was built and be generated with grids using Gambit, the straight nozzle, taper nozzle, sink nozzle, cylinder cavities were simulated and analyzed. Orthogonal test is used to design the test, the cylinder speed, hole diameter and vacuum pressure on the performance indices were analyzed. the results showed that the cylinder speed was 12 r/min, the hole diameter was 3.5 mm, and vacuum pressure was 4.8 kPa. Under the condition of the optimal combination parameters, the quality of feed index, miss index and multiple index were 93 %, 2% and 5%, respectively.