Discharge Characteristics of Powder from Cone Dual Structure Hopper Using Air Vibration

Abstract

We have proposed a new hopper of dual structure which is composed of the cone hard container and the flexible container of soft material. This hopper can avoid the blockage phenomenon of cohesive powder near the orifice using the expansion of flexible container by the vibration of periodic air pressure which changes on the opening and shutting of the solenoid-controlled valve. In this study, we experimentally investigated the effectiveness of this hopper for the discharge of cohesive powder. Also, the effect of the supplied air pressure, the valve timing and the particle properties for the discharge characteristics of this hopper is examined where the flyash of 22.4 μm and the silica sand of 15.6 μm were used for this experiment. It can be confirmed that the dual structure hopper using the air vibration is effective for the discharge of the cohesive powder. Further, it is found that the air pressure and the open time of valve greatly influence the discharge characteristic of the powder.