Conference paper

Editor list: Schwabe, D; Kuhlmann, HC; Croll, A; Colinet, P

Publication year: 2002

Pages: 629-638

Journal: Advances in Space Research

Volume number: 29

Issue number: 4

ISSN: 0273-1177

ISBN: *************

DOI Link: https://doi.org/10.1016/S0273-1177(01)00654-8

Conference: G0 1 Symposium of COSPAR Scientific Commission G held at the 33rd COSPAR Scientific Assembly

Publisher: Elsevier

Title of series: ADVANCES IN SPACE RESEARCH

Abstract: 
We investigated thermocapillary flow in an annular gap with outer heated container of radius R-1 = 40 mm and inner cooled cylinder of R-2 = 20 mm and with an adjustable height h, 2.5 less than or equal to h less than or equal to 20 mm. The gap was filled flat up to the rim with the 0.65 cSt silicone oil hexamethyldisiloxane (Prandtl number Pr = 6.7). The temperature differences DeltaT, 0 K less than or equal to DeltaT < 40 K between outer and inner wall generated thermocapillary flow in the free upper surface and various flow structures have been observed under microgravity. We identified hydrothermal waves for small h and more complicated oscillations for larger h. For small h and small DeltaT the multiroll structure was visible via IR-images of the free surface: concentric steady convection rolls with the same sense of rotation, embedded into the main thermocapillary roll. We measured the critical Marangoni number Ma(c) for the transition to time-dependent flow in the aspect ratio range A = h/(R-1 - R-2), 0.125 less than or equal to A less than or equal to 1, where it was virtually constant Ma(c) approximate to 5 . 10(4). We report and discuss a steady temperature asymmetry, changing its direction from time to time, as recorded by the IR-camera. This symmetry breaking is most probably due to slowly changing residual acceleration in the satellite. (C) 2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Harvard Citation style: Schwabe, D. and Benz, S. (2002) Thermocapillary flow instabilities in an annulus under microgravity - Results of the experiment magia, Advances in Space Research, 29(4), Article PII S0273-1177(01)00654-8, pp. 629-638. https://doi.org/10.1016/S0273-1177(01)00654-8

APA Citation style: Schwabe, D., & Benz, S. (2002). Thermocapillary flow instabilities in an annulus under microgravity - Results of the experiment magia. Advances in Space Research. 29(4), Article PII S0273-1177(01)00654-8, 629-638. https://doi.org/10.1016/S0273-1177(01)00654-8