Nonlinear waves in a falling film with phase transition

Nonlinear wave formation and heat transfer in wavy film flowing over the isothermal wall in the present of phase transition are studied numerically. The integral-boundary-layer model, modified with account of the phase change at the interface has been used to describe the wave motion. For the first time the nonlinear evolution of forced two-dimensional waves was investigated, and wave effect on heat transfer was determined. It is shown that forced waves essentially intensify heat transfer within a certain range of frequencies as compared to the case of naturally occurring waves. 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.