Abstract
Marangoni convection in a silicon melt was investigated from viewpoint of a heat and mass transfer for a low Prandtl number liquid. Temperature measurement and flow visualization in a half-zone bridge of molten silicon were carried out in a microgravity condition using the NASDA TR-IA-6 rocket. Fourier-transformation analysis of temperature fluctuations showed several peak frequencies for the microgravity condition when a Marangoni number Ma was 1900. On the other hand, a single peak was seen when Ma= 1315 in the 1-G reference experiment. It suggests that the transition from non-periodic to periodic flow of the silicon Marangoni convection in a half-zone liquid bridge system exists between these conditions. With using the x-ray radiography, tracer motions in the azimuthal directions were observed near the molten silicon surface. This observation indicated that the tracer motions were driven by the temperature fluctuations in the azimuthal direction.
