Vapour Recoil Effect on a Vapour--Liquid System with a Deformable Interface

A new two-sided model of vapour--liquid layer system with a deformable interface is proposed. In this model, the vapour recoil effect on the Marangoni--Bénard instability of a thin evaporating liquid layer can be examined only when the interface deflexion is considered. The instability of a liquid layer undergoing steady evaporation induced by the coupling of vapour recoil effect and the Marangoni effect is analysed using a linear stability theory. We modify and develop the Chebyshev--Tau method to solve the instability problem of a deformable interface system by introducing a new equation at interface boundary. New instability behaviour of the system has been found and the self-amplification mechanism between the evaporation flux and the interface deflexion is discussed.