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Updated: Jun 7, 2025
08:25
Measurements of Local Instantaneous Convective Heat Transfer in a Pipe - Single and Two-phase Flow
Published on: April 30, 2018
7.1K
A semi-empirical relation based on temperature difference and filling ratio in a closed loop pulsating heat pipe: A
Vasanth Balamurugan1, Shahid Mian P1, Md Jahid Hasan2
1Department of Mechanical Engineering, Rajalakshmi Engineering College, Chennai, Tamil Nadu, India.
Plos One
|November 19, 2024
Summary
This study optimizes closed-loop pulsating heat pipes (CLPHPs) for electronic cooling. A 0.5 volume fraction offers optimal thermal efficiency, enhancing heat transfer by up to 86% with increased evaporator temperature.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Heat Transfer
Background:
- Closed-loop pulsating heat pipes (CLPHPs) are effective passive cooling systems for electronics.
- CLPHP design is complex due to thermo-hydrodynamic coupling.
- Optimizing CLPHP efficiency requires understanding heat transfer characteristics.
Purpose of the Study:
- Investigate the heat transfer efficiency of a CLPHP using water.
- Develop semi-empirical equations for heat transfer rate and heat flux.
- Identify optimal design parameters for improved CLPHP performance.
Main Methods:
- Computational Fluid Dynamics (CFD) simulations were used to evaluate heat transfer.
- Regression analysis was performed on computed results to derive semi-empirical equations.
- Force plots were generated to analyze slug dynamics.
Main Results:
- Semi-empirical equations for heat transfer rate (Q) and heat flux (q) were developed and validated against CFD results.
- A volume fraction of 0.5 was identified as optimal for slug formation and thermal efficiency.
- Heat transfer rate increased by 40-86% with a 15% increase in evaporator temperature at the optimal filling ratio.
Conclusions:
- The developed semi-empirical equations accurately predict CLPHP performance.
- Optimal CLPHP design can significantly enhance cooling efficiency for electronic components.
- Further analysis of slug dynamics aids in optimizing CLPHP design and efficiency.
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