Sharif Journal of Mechanical Engineering

Sharif Journal of Mechanical Engineering

Numerical Study of the Effect of Combining Passive Flow Control Methods to Improve Cyclone Performance

Document Type : Article

Authors
Arman Moghadaszadeh
Saeed Karimian Aliabadi
Faculty of Mechanical Engineering in Tarbiat Modares University
10.24200/j40.2026.67233.1740
Abstract
Cyclones play a crucial role in particle separation from fluid streams due to their high efficiency and low cost. In this study, the performance enhancement of a gas cyclone was investigated through step-by-step geometric modifications. These changes were aimed at improving flow guidance, reducing turbulence fluctuations, and increasing particle-wall interactions to improve overall cyclone performance, a concept referred to in this study as flow control. Initially, the Stairmand cyclone was selected as the baseline model, and its performance was analyzed using numerical simulations with the Reynolds Stress Model (RSM) and the Eulerian-Lagrangian approach in ANSYS Fluent software. A structured mesh was generated, adhering to quality criteria to ensure accurate results. The numerical model was validated against published experimental data, demonstrating good agreement with less than 10% error. Geometric modifications were applied to four main sections of the cyclone: the inlet, vortex finder, body, and collection section. The results showed that the 360-degree turning inlet design, by better guiding the flow and increasing particle-wall collisions, enhanced the separation efficiency by 11.52% and reduced the cut-off diameter by 12.14%, though it caused a 22.04% increase in pressure drop. The addition of a curved vortex finder reduced the pressure drop by 7.49% compared to the first modification and had a positive overall effect. Introducing a cylindrical vortex -
stabilizing rod in the cyclone body reduced flow oscillations and further improved separation efficiency by 1.15% compared to the previous stage. Finally, the implementation of a reverse cone in the collection section enhanced fine-particle separation, reducing the cut-off diameter to 1.3 micrometers. These findings provide a foundation for further cyclone optimizations and highlight the potential for improving their performance in industrial applications.
Keywords
Cyclone
numerical simulation
flow control
separation efficiency
pressure drop
particle diameter
cut-off diameter
Subjects
 
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