Preliminary results from three USML-1 Glovebox experiments

Three simple experiments, namely, Marangoni convection in closed containers (MCCC), fiber pulling in microgravity, and stability of a double float zone are described which were conducted during the U.S. Microgravity Laboratory mission (USML) in July 1992. Results show that, in the MCCC experiment, there was no evidence of partial wetting between the liquid and the walls either in the wetting or nonwetting configuration. In the nonwetting system, the void formed a hemispherical bubble that remained pinned to the walls with considerable contact line resistance. Significant differences were observed in the ability to pull liquid strings in low gravity in those materials which readily form liquid strands in normal gravity and do not necessarily form strands in reduced gravity. The double float zone configuration appeared to be quite stable in both cylindrical and sheet form.