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Updated: Jun 23, 2026
07:32
Pool-Boiling Heat-Transfer Enhancement on Cylindrical Surfaces with Hybrid Wettable Patterns
Published on: April 10, 2017
Development of high-performance cooling devices for space application by using flow boiling in narrow channels
Shinichi Miura1, Yukihiro Inada, Yasuhisa Shinmoto
1Department of Aeronautics and Astronautics, Kyushu University, Nishi-ku, Fukuoka, Japan. miura@aero.kyushu-u.ac.jp
Annals of the New York Academy of Sciences
|May 12, 2009
Summary
Researchers enhanced critical heat flux (CHF) in narrow channel cooling systems by optimizing liquid supply. Higher CHF values were achieved in 2 mm channels at specific flow rates, demonstrating improved heat removal potential for electronics.
Area of Science:
- Thermal Engineering
- Fluid Dynamics
- Heat Transfer
Background:
- Increasing heat generation density in semiconductor devices necessitates advanced cooling solutions.
- Boiling two-phase phenomena offer high heat removal potential, making them attractive for compact cooling systems.
Purpose of the Study:
- To investigate methods for increasing critical heat flux (CHF) in flow boiling within narrow channels.
- To evaluate the impact of improved liquid supply and channel geometry on heat transfer performance.
Main Methods:
- Experiments were conducted using water in a novel narrow heated channel with parallel plates and an auxiliary unheated channel.
- A grooved heated surface (150 mm length, 30 mm width, 90° apex angle, 0.5 mm depth, 1 mm pitch) was utilized.
- Tests involved varying gap sizes (2 mm, 5 mm) and volumetric flow rates, with specific inlet/outlet configurations to ensure stability.
Main Results:
- Critical heat flux (CHF) exceeding 2 x 10^6 W/m^2 was achieved in 2 mm gap channels at volumetric flow rates above 4.5 x 10^-5 m^3/s.
- At higher flow rates ( > 6.0 x 10^-5 m^3/s), dry patch formation occurred upstream in both 2 mm and 5 mm channels.
- Pressure drop increased with flow rate, being higher for the 2 mm gap. However, the 5 mm gap yielded higher CHF for equivalent pump power.
Conclusions:
- The experimental setup successfully enhanced CHF in narrow channels through controlled liquid supply and specific geometric features.
- Channel gap size and flow rate significantly influence CHF and burnout location, with upstream burnout observed at high flow rates.
- Optimizing channel design for specific operating conditions is crucial for maximizing cooling performance within power constraints.
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