DROPS, LIQUID LAYERS AND THE MARANGONI EFFECT

An overview is given of recent results about the onset and development of steady and time-dependent flow motions past an instability thresho ld induced by the Marangoni effect. First, I consider the case of a li quid drop immersed in another immiscible liquid when (endo-or exotherm ic) reaction, heat and/or mass transfer at/across the drop surface, et c., leads to self-propelled drop motion, overcoming viscous drag. Then I recall salient features about the spreading of an immiscible or a d issolving drop (with surfactant) on the surface of another liquid. Fin ally, I consider Benard layers when either steady convective patterns or waves are produced by appropriate heat or mass transfer across the open surface.