Session H6: Drops VI: Thermal Effects
10:30 AM–12:40 PM, Monday, November 21, 2011
Room: 309
Chair: Detlef Lohse, University of Twente
Abstract ID: BAPS.2011.DFD.H6.10
Abstract: H6.00010 : Numerical study of thermocapillary instabilities in evaporating annular pools and sessile droplets
12:27 PM–12:40 PM
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Abstract
Authors:
Pedro J. S\'{a}enz
(University of Edinburgh)
Prashant Valluri
(University of Edinburgh)
Khellil Sefiane
(University of Edinburgh)
George Karapetsas
(Imperial College London)
Omar K. Matar
(Imperial College London)
We investigate thermocapillary flows due to temperature-induced surface tension gradients in annular liquid pools via full two-phase direct numerical simulations in 3D. Phase-change, interface deformation and wettability phenomena are taken into consideration by using a variant of the volume-of-fluid method. The simulation results are validated against experiments (Schwabe et al. 2003 {\&} Riley et al. 1998) and theory (Smith {\&} Davis 1983). The transient results show the evolution of the flow towards an oscillatory state characterized by interfacial hydrothermal waves (HTWs). We present the effects of non-uniform evaporation fluxes and the liquid depths on the linear and non-linear development of these thermocapillary instabilities. The influence on bulk flows, surface temperature patterns and interface deformations are also shown. We finally introduce spontaneously self-excited HTWs in evaporating sessile droplets simulated using novel numerical methods and compare the results against analytical models and experiments.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2011.DFD.H6.10