Nonlinear waves and heat transfer in a falling film of condensate

Nonlinear wave formation and heat transfer in wavy condensate film flowing over the isothermal wall are studied numerically. The integral-boundary-layer model, modified with account of the phase transition has been used to describe the wave motion. The nonlinear evolution of both natural and forced two-dimensional waves was investigated, and wave effect on heat transfer in condensate film was determined. Heat transfer enhancement by waves due to the predominant contribution of the thin residual layer between the peaks was demonstrated. It is shown that by applying the superimposed periodic oscillations, one can intensify heat transfer within a certain range of frequencies as compared to the case of naturally occurring waves. (C) 2013 AIP Publishing LLC.