https://doi.org/10.1140/epje/i2017-11517-5
Regular Article
Onset and non-linear regimes of Soret-induced convection in binary mixtures heated from above
1
Institute of Continuous Media Mechanics UB RAS, 614013, Perm, Russia
2
Perm State University, Bukireva St. 15, 614990, Perm, Russia
3
MRC, CP-165/62, Université Libre de Bruxelles (ULB), Brussels, Belgium
* e-mail: lubimova@psu.ru
Received:
31
August
2016
Accepted:
22
February
2017
Published online:
15
March
2017
The paper deals with the investigation of the onset and non-linear regimes of convection of liquid binary mixtures with negative Soret effect heated from above. The linear stability of a convectionless state in a horizontal layer is studied by the numerical solution of the linearized problem on the temporal evolution of small perturbations of the unsteady base state. Non-linear regimes of convection are investigated by the numerical solution of the non-linear unsteady equations for a horizontally elongated rectangular cavity. The calculations are performed for water-ethanol and water-isopropanol liquid mixtures and for colloidal suspensions. The dependences of the instability onset time and wave number of the most dangerous perturbations on the solutal Rayleigh number (gravity level) obtained by a linear stability analysis and non-linear calculations are found to be in a very good agreement. A favorable comparison with the existing experimental and numerical data is presented.
Key words: Topical Issue: Non-isothermal transport in complex fluids
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2017