Effect of interfacial heat exchange on thermocapillary flow in a cylindrical liquid bridge in microgravity

Abstract

The effect of interfacial heat exchange on thermocapillary flow in a cylindrical liquid bridge of 1 cst silicone oil (with Prandtl number 16.0) with aspect ratio 1.8 in microgravity, was investigated in an extended range of Biot number. With both constant and linearly distributed ambient temperature, the computed results predict that the marginal stability curve for the thermocapillary flow exhibits a roughly convex trend. In the range of small Biot number, however, a sharp local maximum exists with a special oscillation mode of azimuthal wave number m = 0, in contrast to the other cases with m = 1. In addition, the normalized “thermal” energy balance between the basic state and the critical perturbation of the thermocapillary flow was investigated. Finally, the effect of the interfacial heat exchange on the thermocapillary flow in a liquid bridge of low Prandtl number fluid in microgravity was investigated as a comparison.