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Constructal Optimization of Rectangular Microchannel Heat Sink with Porous Medium for Entropy Generation Minimization
Wenlong Li1, Zhihui Xie1, Kun Xi1
1College of Power Engineering, Naval University of Engineering, Wuhan 430033, China.
Entropy (Basel, Switzerland)
|November 27, 2021
Summary
Optimizing microchannel heat sinks (MCHS) with porous media (PM) using constructal theory significantly reduces entropy generation. Aspect ratio and flow direction adjustments minimize heat transfer inefficiencies.
Area of Science:
- Thermodynamics
- Fluid Mechanics
- Heat Transfer
Background:
- Microchannel heat sinks (MCHS) are crucial for thermal management.
- Entropy generation minimization (EGM) is a key principle for optimizing heat transfer devices.
- Porous media (PM) can enhance heat transfer characteristics in MCHS.
Purpose of the Study:
- To develop and optimize a model of a rectangular MCHS with PM.
- To minimize dimensionless entropy generation rate (DEGR) using constructal theory.
- To analyze the impact of various parameters on DEGR.
Main Methods:
- Numerical simulation for optimizing aspect ratio and length-width ratio.
- Application of constructal theory for entropy generation minimization.
- Parametric analysis of Reynolds number, heat flux, porosity, and PM volume proportion.
Main Results:
- Optimal aspect ratios were identified to minimize DEGR, achieving a 33.10% reduction.
- Increased Reynolds number decreased optimal aspect ratio and minimum DEGR.
- Higher heat flux increased DEGR while keeping optimal aspect ratio constant.
- Simultaneous optimization of aspect and length-width ratios yielded a further 10.70% DEGR reduction.
Conclusions:
- Geometric optimization of MCHS with PM is effective in reducing entropy generation.
- Flow direction significantly influences DEGR in rectangular MCHS.
- The study provides insights for designing more efficient heat dissipation systems.
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