Iranian Chemical Engineering Journal

Iranian Chemical Engineering Journal

CFD Simulation to Evaluate the Mixing quality by Mixers with Different Blade Shapes

Document Type : Original Article

Authors
Y. Basereh 1
R. Beigzadeh 2
1 M. Sc. in Chemical Engineering, University of Kurdistan
2 Associate Professor of Chemical Engineering, University of Kurdistan
10.22034/ijche.2024.446615.1402
Abstract
The optimum design of mixing tank reactors is very important to increase the mixing in industries. This study examined how varying operational factors, such as the type and angle of stirring blades, as well as the rotational speed, affect mixing rates. Four types of mixers (Rushton, Smith Turbine, Reversible Rushton, and Reversible Propeller) were modeled using computational fluid dynamics techniques to assess their mixing performance. The study analyzed the effects of varying rotational speeds (20, 40, and 60 rpm) and inlet flow velocities (0.028, 0.03, 0.04, and 0.05 m/s) on the mixing efficiency. The results showed that, among the designed models, the Reversible Rushton has the best mixing rate and the closest behavior to the ideal state. Where θ is equal to 3, its mixing factor is equal to 0.083879. Additionally, it was noted that as the inlet velocity increased, the rate of change in mixing also became more pronounced. It was observed that the Reversible Rushton shows the least sensitivity to the change of rotational speed compared to the other three blades. The Reversible Rushton model at 20 rpm rotational speed and 0.03 m/s inlet velocity demonstrated the highest mixing rate among all investigated cases.
Keywords
Simulation
Computational Fluid Dynamics
Stirred Tank
Blade Shape
Mixing
Subjects
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Iranian Chemical Engineering Journal
Volume 24, Issue 139
July and August 2025
Pages 136-147