Laminar Forced Convection Heat and Mass Transfer of Humid Air across a Vertical Plate with Condensation

• Published in: Chinese journal of chemical engineering Vol. 19; no. 6; pp. 944 - 954
• Main Author: 李成 李俊明
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2011
• Subjects: binary mixture; Chemical engineering; Condensate films; condensation; Condensing; convective heat and mass transfer; Laminar; Mass transfer; Mathematical models; Simplification; Wall temperature; 传热传质特性; 凝结; 垂直; 对流; 数值研究; 板; 气液界面; 潮湿空气; condensation; binary mixture; convective heat and mass transfer
• ISSN: 1004-9541; 2210-321X
• DOI: 10.1016/S1004-9541(11)60076-1

Condensation of humid air along a vertical plate was numerically investigated, with the mathematical model built on the full boundary layer equations and the film-wise condensation assumption. The velocity, heat and mass transfer characteristics at the gas-liquid interface were numerical analyzed and the results indicated that it was not reasonable to neglect the condensate film from the point of its thickness only. The condensate film thickness, interface temperature drop and the interface tangential velocity affect the physical fields weakly. However, the subcooling and the interface normal velocity were important factors to be considered before the simplification was made. For higher wall temperature, the advective mass transfer contributed much to the total mass transfer. Therefore, the boundary conditions were the key to judge the rationality of neglecting the condensate film for numerical solutions. The numerical results were checked by comparing with experiments and correlations.