The Effect of Cyclone Shape and Dust Collector on Gas-Solid Flow and Performance

Numerical analysis of flow characteristics and separation efficiency in a high-efficiency cyclone has been performed. Several models based on the experimental observation for a design purpose were proposed. However, the model is only estimated the cyclone's performance under the limited environments; it is difficult to obtain a general model for all types of cyclones. The purpose of this study is to find out the flow characteristics and separation efficiency numerically. The Reynolds stress model (RSM) was employed instead of a standard k-ε or a k-ω model which was suitable for isotropic turbulence and it could predict the pressure drop and the Rankine vortex very well. For small particles, there were three significant components (entrance of vortex finder, cone, and dust collector) for the particle separation. In the present work, the particle re-entraining phenomenon from the dust collector to the cyclone body was observed after considerable time. This re-entrainment degraded the separation efficiency and was one of the significant factors for the separation efficiency of the cyclone.

Authors:

• Kyoungwoo Park
• Chol-Ho Hong
• Ji-Won Han
• Byeong-Sam Kim
• Cha-Sik Park
• Oh Kyung Kwon

Keywords:

• CFD
• High-efficiency cyclone
• Pressure drop
• Rankine vortex
• Reynolds stress model (RSM)
• Separation efficiency.

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