Characteristics of film condensation of supersaturated steam-air mixture on a flat plate

Experimental and numerical work was performed for the laminar film condensa tion of steam-air mixture flow over a flat plate. For small temperature dif ference between the gas mixture and the cold wall, the gas mixture in the b oundary layer can be treated as superheated gas. When the temperature diffe rence is large, the gas mixture becomes supersaturated near the interface. In that case, mist formed near the interface, the temperature profile of th e gas mixture was greatly concaved toward the interface and the heat transf er was enhanced. However the velocity profile measured by the laser Doppler anemometer (LDA) showed the same trend without mist formation. A calculati on model is proposed and compared with the experimental data and previous m odels for the superheated or the saturated conditions. (C) 1999 Elsevier Sc ience Ltd. All rights reserved.