Marangoni convection has a large effect on materials processing since it remarkably enhances heat and mass transport near a free interface. TO have a better understanding of the behavior of Marangoni convection in molten salts, observation and calculation of the thermal convection in a column held between a pair of Pt disks (2mm in diameter) fixed to hot thermocouples, were carried out. In order to evaluate the degree of contribtion of buoyant convection to the system, a drop shaft facility was used to obtain micro gravity conditions. Marangoni convection flows were observed under both normal gravity conditions and micro gravity conditions. Surface motion was observed to take place from the hot to the cold region due to the temperature coefficient of the surface tension. The influence of micro gravity on the motion was not strong in the experimental conditions used. A main change was observed in the shape of the bridge and flow patterns andfluid velocity. The temeprature increase at the disks was measured during the micro gravity condition. Simulations of the flow patterns and the velocity due to Marangoni convection were carrid out and the results roughly agreed with the experiments.
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