Numerical analysis of bubble migration in thermocapillary flows of an open cylindrical container

Thermocapillary flow is driven by temperature-induced surface tension variations along a liquid free surface. The experiments and the calculations for the flows in open cylindrical containers were carried out both in space and on ground. The detail phenomena have been made clear from these investigations. In 1995, however, numbers of air bubbles were merged incidentally in the cylindrical container and moved along the flows while the Oscillatory Thermocapillary Flow Experiment 2 (OTFE-2) was carried out on the Second United States Microgravity Laboratory (USML-2). These bubbles gradually moved to the flow centers and finally all the distances between two bubbles became almost the same.