CRITICAL HEAT FLUX IMPROVEMENT USING METAL HONEYCOMB POROUS PLATE FORMED BY ELECTROLYTIC DEPOSITION IN A SATURATED POOL BOILING

Enhancement of pool boiling heat transfer using a copper honeycomb porous plate (HPP) made by electrolytic deposition has been experimentally examined. The critical heat flux (CHF) could be enhanced to 3.7 MW/m² which is three times of plain surface at most. The thicker the porous material prepared by electrodeposition, the CHF is enhanced. Moreover, the effect of the shape of HPP and the wickability on CHF were examined in this paper. Electrolytic deposition makes copper porous structure having porous part with pores about 10~20µm diameter and vapor escape channel which are 0.1~0.5mm in diameter. Vapor escape channels affecting wickability are formed by hydrogen bubbles generated during electrolytic deposition. Experimental results show that CHF increases with increasing wickability in thick porous plates as well as thin ones. In Addition, unlike the porous materials used to date, the CHF also continued to increase with increasing thickness, up to a sufficiently thick condition of 2 mm.