Characteristic of boiling heat transfer coefficient for porous metal fins

Abstract

Porous metal fin was used as boiling heat transfer plate of phase change devices. The number of cells of the porous metal fin is 8 ppi, and the pore diameter of the porous metal fin is 3.1 mm. On the boiling heat transfer surfaces, the porous metal fin and the bass plate are brazed. Three samples of boiling heat transfer plates with the porous metal fin were made as prototype. For HFE7000 and HFE7100 made by 3M Company as working fluid, the boiling heat transfer coefficient of the boiling heat transfer plate with porous metal fin with surface roughing process by ultrasonic wave is 15 kW/m2･K. And the vale is 2.5 times of the boiling heat transfer coefficient of the flat plate without fin. Predicting method of the boiling heat transfer coefficient to which the expansion ratio of effective area for the flat plate was added to correlation of the boiling heat transfer coefficient of Stephan’s equation. The boiling heat transfer coefficient in the heat transfer plate with surface roughing process by ultrasonic wave can be put in order by ± 10 %.

Keywords

• porous metal fin
• boiling
• heat transfer coefficient
• prediction method
• refrigerant