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Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel
Published on: October 5, 2018
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Entropy Generation and Mixed Convection Flow Inside a Wavy-Walled Enclosure Containing a Rotating Solid Cylinder and
Ammar I Alsabery1,2, Tahar Tayebi3,4, Rozaini Roslan5
1Refrigeration & Air-conditioning Technical Engineering Department, College of Technical Engineering, The Islamic University, 54001 Najaf, Iraq.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
This study explores heat transfer and fluid flow in a wavy chamber with a rotating cylinder. Controlling cylinder rotation significantly impacts fluid dynamics and entropy generation, with near-stationary cylinders maximizing the Bejan number.
Area of Science:
- Computational Fluid Dynamics (CFD)
- Heat Transfer
- Thermodynamics
Background:
- Investigates mixed convection within a complex geometry: a wavy-walled chamber.
- Includes a rotating inner cylinder and a localized heat source on a vertical wall.
- Examines entropy production, a key thermodynamic performance indicator.
Purpose of the Study:
- To analyze the 2D entropy production and mixed convection phenomena.
- To understand the influence of parameters like Rayleigh number, cylinder rotation, and heat source length on fluid flow and heat transfer.
- To determine how to control fluid flow and optimize thermal performance.
Main Methods:
- Governing equations and boundary conditions were non-dimensionalized.
- The weighted residual finite element method (Galerkin method) was employed for numerical solution.
- Mesh independence tests and validation against benchmark solutions ensured accuracy.
Main Results:
- Fluid flow characteristics, including stream function, isotherms, and entropy lines, were visualized.
- The angular rotational velocity of the inner cylinder was identified as a key parameter for controlling fluid flow.
- The Bejan number peaked when the inner cylinder was nearly stationary, across all oscillation numbers.
Conclusions:
- The study successfully demonstrates the controllability of fluid flow via inner cylinder rotation.
- Optimal conditions for minimizing entropy generation and enhancing thermal performance can be achieved through parameter manipulation.
- The findings provide valuable insights for designing systems involving heat transfer and fluid flow in wavy geometries.
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