Fabrication and experimental investigation of the bionic vapor chamber. (5th March 2020)

• Record Type: Journal Article
• Authors: Luo, Yuanqiang; Liu, Wangyu; Huang, Guangwen
• Is Part Of: Applied thermal engineering. Volume 168(2019)
• Publication Date: 2020-03-05
• Subjects: Heat dissipation -- Bionic vapor chamber -- Fractal network microchannels -- Copper foam -- Porosity gradient -- Laser engraving; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2019.114889
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: A new type of bionic vapor chamber was designed and manufactured. The wick structure combined the fractal network microchannels and copper foam. The porosity gradient of the copper foams around the fractal microchannels was added. The fractal network microchannels were processed by laser engraving and mould coining. Keff of the bionic vapor chamber was higher than most existing vapor chambers. Abstract: With the rapid development of photoelectric products, their miniaturization and high integration have intensified the problem of heat dissipation. In this paper, a new type of bionic vapor chamber is designed and manufactured. The wick structure for the condenser combines the fractal network microchannels and copper foam, which are used to imitate the macroscopic leaf vein network and microscopic mesophyll tissue, respectively. Furthermore, the permeability gradient distribution between the leaf veins and mesophyll tissue is added, presented as the porosity gradient distribution of the copper foams around the fractal network microchannels. Then the fractal network microchannels on the wick are processed by laser engraving and mould coining, respectively. The wick structure for the evaporator is homogeneous copper foam. The minimum value of the maximum temperature difference on the upper surface of the condenser of the bionic vapor chamber is only 1.21 K and that of the overall thermal resistance of the bionic vapor chamber is only 0.094 K/W. Compared with the existing novel vapor chambers, when using deionized water as the working fluid, the maximum through-plane effective thermal conductivity and minimum in-plane effective thermal conductivity are 9.52 W/m·K and 10500 W/m·K, respectively, which are higher than most existing vapor chambers.