RESEARCH OF SEED GROUP STRUCTURE CHARACTERISTICS OF VERTICAL DISC METERING DEVICE BASED ON DISCRETE ELEMENT METHOD

Abstract

The vertical disc seed metering device was selected to study the influence of the structural characteristics of seed group on the filling performance of seed metering device. The working process of seed metering device was simulated by discrete element software to study the influence of seed quantity and structure characteristics of seed chamber on seed movement and filling results. The seed group was divided into four zones: ascending zone, relative static zone, collapse zone and recirculation zone. The number of seeds and the rotation speed of disk have no effect on the inclination angle of the recirculation zone upper surface, which was always about 35°. But they had a significant effect on the filling performance. When the number of seeds was 500-1500, QFI (quality of feed index) decreased, MIS (miss index) increased and MUL (multiple index) did not change significantly. However, when the number of seeds was 2000, the change trend of filling performance was completely opposite. Inner surface inclination angle and axial width of the seed chamber have significant effects on the filling performance. QFI first increased and then decreased with the increase of inclination angle, reaching the maximum at 20° and MIS showed the opposite trend. QFI increases with the increase of thickness and tends to be stable at 40mm. Similarly, MIS has the opposite trend.