Numerical Study of the Effect of Rotation on Backward-Facing Step

Abstract:

A numerical simulation of the effect of rotation on mixed convection laminar flow with separation and reattachment length is studied. The channel is subjected to span-wise Rotation. The working fluid was air with the prandtl number of 0.71. The governing equations are solved with a finite element-based commercial solver, COMSOL Multiphysics. The influence of the Reynolds number and angular velocity Ω on the fluid flow and heat transfer characteristics is numerically studied. Range varies Reynolds number (100 ≤ Re ≤ 500), Richardson number (0.1 ≤ Ri ≤ 10), and angular velocity Ω (0, 10, 20, 30). The Nusselt number, pressure drop, recirculation length, and total flow rate were calculated. The calculated results span a wide parameters set, particularly from low rotational speed to high rotational speed. The Nusselt number, pressure drop, and patterns are shown. When comparing the results of the standard BFS case with the rotating BFS case in a step facing backward, the Heat Transfer Enhancement was 3% present obtained for rotation of Ω=30 at the Reynolds number Re=500.

• Periodical: Engineering Headway (Volume 8)
• Pages: 25-38
• DOI: https://doi.org/10.4028/p-nEn027
• Online since: June 2024
• Authors: Ghaidaa Kareem Rahi, Dhafer Hamza
• Keywords: Rotation Backward-Facing Step, Rotation Channel

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