Experiments on thermocapillary instabilities

This review summarizes recent experimental studies of instabilities in free -surface flows driven by thermocapillarity. Two broad classes are considere d, depending upon whether the imposed temperature gradient is perpendicular (Marangoni-convection instability) or parallel (thermocapillary-convection instability) to the free surface. Both steady and time-dependent instabili tes are reviewed in experiments employing both large- and small-aspect-rati o geometries of various symmetries.