Numerical study of the evaporative cooling of liquid film in laminar mixed convection tube flows

A numerical study is reported to investigate the evaporative cooling of liquid film falling along a vertical tube. A marching procedure is employed for solution of the equation of mass momentum, energy and concentration in the flow. Numerical results for air-water system are presented. The effects of flow conditions on the film cooling mechanism are discussed. Results show that a better liquid film cooling is noticed for a system having a higher inlet liquid temperature T-Lo, a higher gas flow Reynolds number Re or a lower liquid flow rate Gamma (o). Additionally, the results indicate that the convection of heat by the flowing water film becomes the main mechanism for heat removal from the interface. (C) 2001 Editions scientifiques et medicales Elsevier SAS.