SIMULATION STUDY ON SOYBEAN WINNOWING BASED ON CFD–DEM COUPLING

To address the issues of high impurity content and seed loss in soybean cleaning, this study employs a CFD–DEM coupled simulation using SN52 soybeans and a single-factor experimental design to analyze the air winnowing process under different inclination angles, inlet air velocities, and inlet opening sizes. The results indicate that, at an inlet air velocity of 17 m/s and an inlet opening size of 220 mm, the impurity rate decreases with increasing inclination angle, while the loss rate first decreases and then increases. When the inclination angle is 21° and the inlet opening size is 220 mm, the impurity rate decreases with increasing inlet air velocity, with the loss rate again showing an initial decrease followed by an increase. Similarly, at a 21° inclination angle and an inlet air velocity of 17 m/s, the impurity rate decreases as the inlet opening size increases, while the loss rate exhibited the same initial decrease and subsequent increase. The optimal parameter combination is determined to be 17 m/s inlet air velocity, 21° inclination angle, and 220 mm inlet opening size, achieving an impurity rate of 1.59%, a loss rate of 0.26%, and a cleaning efficiency of 98.15%. These findings provide a theoretical basis for the optimized design of airflow-based soybean cleaning equipment.