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Gradient-Wettable Multiwedge Patterned Surface for Effective Transport of Droplets against the Temperature Gradient
Jingjing Zhai1, Jie Zhang1, Liyuan Xu1
1College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics & Astronautics, Nanjing 210016, China.
ACS Applied Materials & Interfaces
|November 4, 2024
Summary
This study introduces a novel gradient-wettable surface designed for efficient heat dissipation in electronics. The patterned surface enhances droplet transport, overcoming challenges posed by temperature gradients in electronic cooling systems.
Area of Science:
- Materials Science
- Fluid Dynamics
- Heat Transfer
Background:
- Stringent requirements for electronic cooling due to rapid advancements in integration technology.
- Heat dissipation equipment stability is crucial for electronic devices.
- Gas-liquid two-phase heat transfer surfaces are vital for efficient cooling.
Purpose of the Study:
- Investigate high-efficiency gas-liquid two-phase heat transfer surfaces.
- Address limited liquid transport performance caused by temperature gradients.
- Develop surfaces with enhanced droplet transport capabilities for electronic cooling.
Main Methods:
- Combined wetting gradient and shape gradient to create a gradient-wettable multiwedge patterned surface.
- Designed multiwedge hydrophilic patterns and adjusted hydrophobic region wetting properties.
- Investigated the effect of average wetting gradient on droplet transport performance.
- Provided theoretical analysis for temperature gradient resistance.
Main Results:
- Demonstrated long-distance and high-velocity droplet transport using the patterned surface.
- Showcased superior temperature gradient resistance compared to conventional surfaces.
- Achieved droplet transport of ~38 mm at an average speed of ~158 mm/s under a 0.59 °C/mm temperature gradient.
Conclusions:
- Gradient-wettable multiwedge patterned surfaces effectively resist hindering temperature gradients.
- The developed surfaces offer improved droplet transport for heat dissipation applications.
- Provides insights for applying temperature gradient resistance in electronic cooling solutions.
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