Performance Study of a Leaf-Vein-like Structured Vapor Chamber

Area of Science:

• Materials Science
• Thermal Engineering
• Optoelectronics

Background:

• Rapid advancements in optoelectronic products necessitate enhanced heat dissipation solutions due to miniaturization and high integration.
• Vapor chambers are established passive devices for efficient heat exchange in electronic cooling systems.

Purpose of the Study:

• To design and manufacture a novel vapor chamber utilizing cotton yarn as a wick material with a fractal leaf vein pattern.
• To comprehensively analyze the thermal performance and anti-gravity capabilities of the developed vapor chamber.

Main Methods:

• Fabrication of a new vapor chamber incorporating cotton yarn wicks and a fractal leaf vein structure.
• Performance evaluation under natural convection, including thermal resistance measurements at various orientations and thermal loads.
• Scanning Electron Microscopy (SEM) to characterize the wick structure.
• Investigation of the effects of vacuum degree and fill amount on performance.

Main Results:

• SEM confirmed the porous capillary structure of cotton yarn fibers, suitable for wick applications.
• The cotton yarn wick exhibited favorable thermal and fluid flow characteristics, leading to significant heat dissipation.
• The vapor chamber achieved a low thermal resistance of 0.43 °C/W at 8.7 W thermal load.
• Excellent anti-gravity performance was observed, with minimal thermal resistance variation across different tilt angles (max difference of 0.06 °C/W).

Conclusions:

• The proposed vapor chamber with cotton yarn wicks offers a promising and cost-effective thermal management solution for mobile electronic devices.
• The study provides a novel approach for selecting wick materials and designing vapor chambers for enhanced cooling performance.