关键词: 水稻脱出物, 旋风清选, 计算流体力学, 分离效率, 试验

Abstract: Cyclone cleaning device is often used in small rice combine harvester. Its key design is to reduce the impurity rate on the premise of assuring lower cleaning loss percentage. In order to explore the  2 phase flow regulation between airstream and kernel  in the segregating cartridge, three-dimensional numerical simulation of cyclone separation and cleaning device was carried out  using Fluent software to analyze grain, rice hull, immature grain and miscellaneous grain in 4LZ-0.8 rice combine harvester cleaning system. The particle trajectories of each mixture in the model were selected and the separation efficiency was calculated. The loss rate and cleaning rate of grain were also tested in bench to evaluate the relationship between cleaning performance with the following 3 factors: winnower fan speed, vacuum fan speed and entrance height of detach components. At the same time, the combination of optimal parameter was found by multi-objective optimization solving with regression model. While the winnow speed was 1 163 r/min, the suction fan speed was 1 920 r/min, the entrance height of separation components was 63.26 mm, and the predicting cleaning rate was 99.26%, which provided references for the redesign of cleaning device.

Key words: rice extractions, cyclone cleaning, computational fluid dynamics, separation efficiency, experiment