A STUDY ON THE INFLUENCING FACTORS OF CORN KERNEL COLLISION RESTITUTION COEFFICIENT BASED ON THE OBLIQUE IMPACT COLLISION THEORY

Corn kernels collide with the pipe wall during pneumatic conveying, which affects their quality. Based on the theory of oblique impact collision dynamics, this paper investigates the breakage of corn kernels at impact angles ranging from 10°~40° and impact velocities ranging from 6 ~ 28m/s. The results show that secondary collisions have a significant effect on the normal restitution coefficient. As the impact angle increases, all three restitution coefficients tend to increase. At impact angles of 40° and above, the normal and overall restitution coefficients are related to the initial velocity, while the tangential restitution coefficient is not. At impact angles of 30° and above, the normal restitution coefficient is smaller at the top and larger in the middle, and the tangential and overall restitution coefficients are independent of the collision location. The three restitution coefficients when the rotation direction is in the same plane are all smaller than those when rotation occurs perpendicular to the translational plane, with the normal restitution coefficient being most affected by the direction. When the impact angle is between 30°~40°, the tangential restitution coefficient of corn kernels increases with increasing rotational speed. When the impact angle is between 20°~40°, the normal restitution coefficient decreases with increasing rotational speed. When the impact angle is between 10°~40°, the overall restitution coefficient is independent of the rotational speed.