Influence of grain discharge rate on the normal force of arch

The arch stress of grain particles during the discharge of the silo is very important to the safety of the silo. At present, most silos adopt the standard discharge port size. To improve the discharge efficiency, it is generally achieved by changing the angle of the discharge port. In this article, an improved silo model is used to study the discharge experiments in the silo with five inclination angles of the discharge port, and analyze the normal force distribution of the wheat grains at the arch, comparing the normal force distribution under five different discharge rates. From the results given, when the angle of the discharge port is 45°, the area where the normal force among particles is larger is wider. At other flow rates, increasing the flow rate can shorten the arching period. During the arching cycle, the normal force among particles in the center area of the silo at the same height is smaller than at the silo wall and is negatively correlated with the discharge rate. In addition, the normal force on the silo wall gradually decreases with the increase in the discharge rate.