Wave flow of the evaporating liquid film

Abstract

Nonlinear wave formation and heat transfer in a laminar falling liquid film in the presence of evaporation are studied numerically. The integral boundary layer model, modified with account of the phase change has been used to describe the wave motion. Numerical simulation of waves in a non isothermal film flow in the presence of evaporation Nonlinear wave formation and heat transfer in a laminar falling liquid film in the presence of evaporation are studied numerically. The integral boundary layer model, modified with account of the phase change has been used to describe the wave motion. Numerical simulation of waves in a non isothermal film flow in the presence of evaporation on an interface is carried out. It is shown that the natural waves caused by instability of flow occur on a surface of evaporating liquid film. For the first time the authors studied the evolution of excited waves in an evaporating film. It is shown that the forced waves occur on smaller distance, than natural ones. The amplitude of the developed waves drops with distance increase. Heat transfer wave intensification is mainly caused by decrease of a film thickness between peaks. Local Nusselt number is determined by distance between the peaks which increases at interaction and merging of some peaks. It is shown that the forced waves intensify essentially heat transfer within a certain range of frequencies in comparison with the naturally occurred waves.

Keywords

• liquid film
• evaporation
• nonlinear waves
• heat transfer
• numerical simulation