The Secondary Flows in a Cyclone Separator: A Review

Abstract

A cyclone separator holds significant importance as the primary gas–solid separation apparatus in the industrial sector. Cyclone separators operate based on a fundamental principle, primarily harnessing the centrifugal force produced by the rotation of air in order to segregate solid particles from the gas stream and then collect them. In addition to the main vortex in the flow field, there are a number of secondary flows, which significantly impact the aggregation of fine particles and contribute to the heightened energy consumption. This paper provides a summary of the three secondary flows in a cyclone separator. These include the recirculation flow in the annular space, which is greatly influenced by the inlet particle concentration. Additionally, the short-circuit flow occurs beneath the vortex finder as a result of the collision between the incoming flow and the rotating flow. Furthermore, the eccentric circumfluence is defined as the deviation of the rotation center caused by the interaction between the upward and downward flows near the discharge. This paper aims to establish a theoretical framework to investigate the flow pattern tracking and the mitigation of secondary flows in order to enhance the operational efficiency of cyclone separators.