Thermocapillary flows in long liquid bridges under microgravity

The problem of the axisymmetrical thermocapillary convection in a long liquid bridge (aspect ratio L/R = 5) is considered. It is found that if the Marangoni number increases the stationary flow turns to the oscillatory multi-roll flow. The dependence of the critical Marangoni number on the aspect ratio is determined. It is shown that the transition from the stationary flow to the oscillatory flow is a Hopf's bifurcation. Further numerical calculations are made in order to determine the characteristic time for a forthcoming microgravity experiment on the sounding rocket MAXUS-4 (spring 2001). (C) 2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.