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  • The effect of phase change on stability of convective flow in a layer of volatile liquid driven by a horizontal temperature gradient
Title: The effect of phase change on stability of convective flow in a layer of volatile liquid driven by a horizontal temperature gradient
Buoyancy–thermocapillary convection in a layer of volatile liquid driven by a horizontal temperature gradient arises in a variety of situations. Recent studies have shown that the composition of the gas phase, which is typically a mixture of vapour and air, has a noticeable effect on the critical Marangoni number describing the onset of convection as well as on the observed convection pattern. Specifically, as the total pressure or, equivalently, the average concentration of air is decreased, the threshold of the instability leading to the emergence of convective rolls is found to increase rather significantly. We present a linear stability analysis of the problem which shows that this trend can be readily understood by considering the transport of heat and vapour through the gas phase. In particular, we show that transport in the gas phase has a noticeable effect even at atmospheric conditions, when phase change is greatly suppressed.  more » « less
Award ID(s):
1511470
PAR ID:
10189605
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Fluid Mechanics
Volume:
838
ISSN:
0022-1120
Page Range / eLocation ID:
248 to 283
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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