小区小麦联合收获机清选系统的仿真分析

Simulation analysis of the district wheat combine harvester cleaning system

采用FLUENT软件对小区小麦联合收获机清选筒内部气相流场和颗粒的运动状况进行了三维数值仿真模拟,利用RNGk-ε方程模拟其中的气相流场,利用DPM模型模拟小麦颗粒和颖壳在清选筒中的运动.通过改变清选筒入口位置、入口大小和喂入速度3个因素,对其分离效率进行对比分析,结果表明:3个因素对清选系统分离效率影响程度的主次顺序依次是入口位置、入口大小、喂入速度;以入口位置395mm、喂入速度9m·s-1、入口大小65mm×100mm确定的清选系统清选效果较好.

The gas flow field and the motion state of wheat inside the cleaning tube of district wheat combine harvester were simulated by the software FLUENT, the gas flow field was simulated by RNG k-εand equation while the motion of wheat grain and glume were simulated by DPM model. And the separation efficiency of cleaning tube was analyzed by changing the entrance location, the size of the entrance and the feeding rate. The results showed that the effect of these three factors on the separation efficiency of the cleaning system taken the following order： the entrance location, the size of the entrance, then the feeding rate;the separation efficiency of the cleaning system determined by the entrance position z=395 mm, the feeding rate v=9 m·s^-1, the entrance size 65 mm×100 mm was superior.