Bionic Boiling Surface Inspired by Leaf Stomata

Area of Science:

• Materials Science and Engineering
• Heat Transfer and Thermodynamics
• Biomimetic Design

Background:

• Effective boiling heat transfer is crucial for energy conversion, refrigeration, and thermal management systems.
• Current large-scale fabrication of enhanced boiling surfaces faces significant challenges.
• Innovative surface structures are needed to improve heat transfer efficiency and critical heat flux (CHF).

Purpose of the Study:

• To design and fabricate a novel bionic boiling surface (BBS) inspired by plant stomata for enhanced heat transfer.
• To investigate the boiling heat transfer performance of the BBS, focusing on nucleation sites and bubble dynamics.
• To demonstrate the potential of the BBS for improving critical heat flux (CHF) in thermal management applications.

Main Methods:

• Developed a nickel bionic boiling surface (BBS) with finger-like pores using the phase-inversion tape casting method.
• Investigated bubble release mechanisms and nucleation site density on the BBS.
• Conducted experimental measurements of boiling heat transfer coefficients and critical heat flux (CHF).

Main Results:

• The BBS demonstrated efficient bubble guidance and timely release due to its straight pore structure.
• Abundant nucleation sites on pore walls promoted nucleate boiling and increased heat transfer coefficient.
• The BBS achieved a critical heat flux (CHF) of 242.6 W/cm², a 163% increase over plain surfaces.

Conclusions:

• The biomimetic design effectively enhances boiling heat transfer by optimizing bubble dynamics and nucleation.
• Capillary forces from surrounding micropores improve wettability and significantly increase critical heat flux (CHF).
• The developed phase-inversion tape casting method enables large-scale manufacturing of high-performance boiling surfaces.