Computational fluid dynamics simulation of the flow patterns and performance of conventional and dual-cone gas-particle cyclones

Document Type : Full Lenght Research Article

Authors

Faculty of Mechanical Engineering, Semnan University, Semnan, Iran

Abstract

One of the main concerns of researchers is the separation of suspended particles in a fluid. Accordingly, the current study numerically investigated the effects of a conical section on the flow pattern of a Stairmand cyclone by simulating single-cone and dual-cone cyclones. A turbulence model was used to analyze incompressible gas-particle flow in the cyclone models, and the Eulerian–Lagrangian approach was employed to examine particle movement. Despite the simplicity of cyclone geometry, internal two-phase flow in such devices is very complicated and anisotropic. This flow was therefore analyzed using a Reynolds stress model. The numerical results were then compared with those of experimental studies. To track calcium carbonate particles, drag and gravity forces were considered in the Lagrangian model. The findings indicated that adding a second conical section at the bottom of the cyclones increases tangential velocity and expands the Rankine vortex region. Moreover, an increasing trend of descending flow occurs. Increasing the number of conical sections elevates pressure drop at all velocities. Finally, the dual-cone cyclone has higher efficiency than the typical cyclone because the smaller end of the former limits particle motion and increases collection performance.

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