The Experimental Investigation on the Transpiration Cooling

Abstract

In this paper, the effectiveness and the coefficient of heat transfer with the transpiration of distilled water and air across the porous plate are discussed. The conditions selected for the experiments were as follows : Velocity of bulk flow is 5∼35 m/sec Temperature of bulk flow is 100∼600°C Mass flow ratio is 0.05∼10% From this investigation the following conclusions have been obtained : 1) Water is more excellent than air as coolant and the difference in cooling effect between air and water is considerable in the range of little mass flow ratio, 2) Nusselt number with transpiration of water is larger than that for solid plate and Nusselt number increases with the mass flow ratio in our experimental investigation, 3) Nusselt number with transpiration of water is nearly in proportion to R₆^4/5 for the constant mass flow ratio.