Impact of entrance angle of rectangular openings of centrifugal multivortex device on its classification efficiency

Abstract

Air classification is a common process in many industries. The paper presents an analysis of the operation of a centrifugal multivortex classifier designed to separate solid particles. The classification process of gas-solid system is observed between the outer pipe and the inner pipe, which has rectangular openings that provide the formation of the stable vortex system. The purpose of this work is to study the influence of the entrance angle of rectangular openings on the classification effectiveness of the device. The results show that the maximum effectiveness in the classification of particles larger than 40 μm is achieved at an angle of 0.8 and a gas flow speed of 16 m/s, providing an effectiveness of 69.6%. Increasing the speed at the inlet to the device improves the effectiveness, since the vortex structure in the interpipe space becomes more stable. It is recommended to select the classifier with the largest entrance angle of rectangular openings, since the lowest pressure loss is achieved. Changing the entrance angle of rectangular openings of the device has practically no effect on the effectiveness of particle classification.