PLATEAU-EXPERIMENTS ON THERMOCAPILLARY CO NVECTION

Investigations on Marangoni-convection in an earthbound laboratory are limited by the fact that the interfacial forces have a smaller order of magnitude than volume forces. With the relevant dimensionless numbe rs: Reynolds-, Marangoni- and the dynamical Bond number, characteristi cs are given for physical similarity, while the static Bond number is a characteristic number for the geometric similarity of diverse experi mental configurations. Interfacial forces are dominant if the Bond num bers are small with respect to one. Thus experimental research on inte rfacial phenomena can be carried out in case of (a) microgravity exper iments, (b) small characteristic dimensions and (c) simulation experim ents using liquids having small density differences (Plateau-simulatio n). By means of a Plateau arrangement the thermocapillary convection i n a liquid drop has been dealt with. Observations of photographically documented convective flow shapes are communicated and discussed.