Paper SS-ThA10
The Critical Marangoni Number Dependence with Different Aspect Ratio Comparing Microgravity Experiments and Numerical Simulation

Thursday, November 1, 2012, 5:00 pm, Room 22

Marangoni experiments with a large diameter, 50 mm, were carried out under microgravity condition in Japanese Experiment Module to make clear critical Marangoni number dependence in liquid bridge configuration such as liquid bridge aspect ratios(length/diameter of liquid bridge). The experiments with the different aspect ratios (length/diameter of liquid bridge) were changed from 0.25 to 1.2 which determined each critical Marangoni numbers. The critical Marangoni numbers decreased up to around 0.4, and after that the number increased monotonically up to 1.2. The most smallest number is observed at critical Mac(20000) at 0.4 and the maximum is Mac (50000) at 1.2. The large liquid bridge was vibrated by crew activity, so that all experiments were done during crew sleeping. This behavior can be qualitatively explained by considering thermal boundary layers which form at both heating and cooling desks of the liquid bridge. The experimental data were good agreement with the numerical results.