Biomimetic luffa copper wicks with extraordinary pool boiling heat transfer performance

Achieving efficient thermal management for ultra-high heat flux applications is a significant challenge. Heat dissipation continues to be a major obstacle in the development of electronic components. While pool boiling heat transfer with wick material offers a promising solution, attaining a pool boiling heat transfer capacity of over 500 W/cm2 remains a daunting task. This study draws inspiration from nature and employs electrochemical techniques to fabricate a series of biomimetic luffa copper wicks, each with a thickness of 570 mu m. These biomimetic luffa copper wicks feature straight channels and porous walls that facilitate bubble departure and liquid supplementation during pool boiling. The controllable channel diameter enables the directional induction of fluid-wetting properties and bubble behavior. Larger channels reduce bubble nucleation superheat, increasing both bubble departure frequency and departure diameter, resulting in an optimal boiling heat transfer coefficient of 52.8 W/cm2 & sdot;K, an 820 % increase compared to smooth surfaces. On the other hand, smaller channels have a significantly greater promoting effect on capillary performance. After all, the contradictory behavior of liquid and bubble behavior of the small channel samples ultimately removes a critical heat flux higher than 550 W/cm2 at a superheat lower than 20 degrees C.