A non-uniform wetting surface with fractal properties and its preparation method

Abstract

The invention relates to a nonuniform wetted surface with a fractal characteristic and a preparation method thereof. The nonuniform wetted surface comprises hydrophobic lattice areas and hydrophilic channels, wherein the hydrophobic lattice areas are distributed according to the fractal characteristic of a Sierpinski carpet curve, and the hydrophilic channels are staggered and pass through the hydrophobic lattice areas so as to form the nonuniform wetted surface. Hydrophobic lattices are distributed according to the fractal characteristic of the Sierpinski carpet curve, so that the boiling heat transfer coefficient is increased, additionally, the nucleating point and the moving and merging direction of steam bubbles can be planned, and the heat flux distribution characteristic in an electronic chip cooling process is combined, so that the forming of the steam bubbles in the high-heat flux density area in the center of a chip and the boiling heat exchange are effectively promoted. The hydrophilic channels can supply sufficient liquid working media, so that the steam bubble film forming is delayed, and the critical heat flux density is increased. The surface has the advantages of high critical heat flux density of hydrophilic areas and high boiling heat transfer coefficient of hydrophobic areas, and the consistent steam bubble distribution and heat flux density distribution of acooling surface can be realized, so that the boiling heat exchange is further intensified.

Description

technical field [0001] The invention belongs to the field of thermal control of electronic devices, and in particular relates to a non-uniform wetting surface with fractal properties and a preparation method thereof. Background technique [0002] Using the latent heat of phase change during boiling heat exchange to obtain higher heat dissipation efficiency has become the most promising technical route in the field of electronic device cooling. In terms of adjusting wettability to enhance boiling heat transfer, the strong wettability of the hydrophilic surface can strengthen the critical heat flux, but high superheat is required to enter nucleate boiling; the opposite is true for the hydrophobic surface, the critical heat flux is lower, but Boiling heat transfer coefficient is high. [0003] In order to combine the advantages of hydrophilic and hydrophobic surfaces to strengthen HTC and CHF at the same time, different numbers of hydrophobic points with the same size are even...

AI Technical Summary

Problems solved by technology

This can reduce the randomness of the bubble nucleation and growth process, but it does not conform to the actual situation of the heat flux density distribution in the center of the heat dissipation surface, which is high and low, and does not conform to the consideration of the kinetic process of the bubble growth and merging mesoscale changes

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