Marangoni--Bénard Instability with the Exchange of Evaporation at Liquid--Vapour Interface

A new two-sided model rather than the one-sided model in previous works is put forward. The linear instability analysis is performed on the Marangoni--Bénard convection in the two-layer system with an evaporation interface. We define a new evaporation Biot number which is different from that in the one-sided model, and obtain the curves of critical Marangoni number versus wavenumber. The influence of evaporation velocity and Biot number on the system is discussed and a new phenomenon uninterpreted before is now explained from our numerical results.