Numerical Analysis for a Falling Liquid Film with Interfacial Waves on an Inclined Plate. Part 2: Effects of Interfacial Waves on Flow Dynamics and Heat Transfer

摘要

Flow and temperature fields in falling liquid films with interfacial waves have been obtained by means of a numerical simulation in which the algorithm is based on the HSMAC method and interfacial boundary conditions are treated with newly proposed methods. Small-amplitude disturbance waves at a low frequency develop into isolated solitary waves which are composed of a roll wave and capillary waves. Waves disturbed at a high frequency interfere with each other and develop into disordered waves. Circulation flow is observed in the roll wave, while, there is no circulation flow in the disordered waves. Temperature fields in the wavy film are distorted by convection effects and differ greatly from these in the laminar film. The The interfacial waves enhance the heat transfer by two kinds of effects: the variation of film thickness and convection in the film. The dominating effect depends on the Prandtl number.