The oscillatory longwave Marangoni convection in a thin film heated from below

A novel type of Marangoni convection was predicted theoretically a decade ago. The thin liquid film atop a substrate of low thermal conductivity was considered. In the case of heating from below, the Marangoni convection emerges not only in a conventional stationary regime, but also as oscillatory flows. Specifically, the oscillatory Marangoni convection emerges if (1) the heat flux from the free surface is small, and (2) the large-scale deformation of the free surface is allowed. During the past decade, this novel Marangoni convection was detected and investigated in several other theoretical works. The review discusses the recent achievements in studying the oscillatory Marangoni convection in a thin film heated from below. The guiding data for observation of the oscillatory regime are also provided. Several recent theoretical works reveal the oscillatory Marangoni instability in thin liquid film atop a heated substrate. The oscillatory regime of convection can be observed in ultrathin films (~ 0.01 mm for water) or under microgravity conditions. The surface tension should allow interface deformations, and the heat transfer from the liquid to the ambient gas should be small.