Nonlinear Convective Oscillations in Two-Layer Systems with an Interfacial Heat Release

Paper number

IAC-13,A2,4,5,x19746

Coauthor

Prof. Ilya Simanovskii, TECHNION - Israel Institute of Technology, Israel

Coauthor

Prof. Antonio Viviani, Seconda Universita' di Napoli, Italy

Coauthor

Mr. Frank Dubois, Université Libre de Bruxelles, Belgium

Coauthor

Prof. Jean-Claude Legros, Université Libre de Bruxelles, Belgium

Year

2013

Abstract

The interfacial convection in two-layer systems is a widespread phenomenon that is of
great importance in space technologies. A scientific interest in such systems is due to the
fact that the interfacial convection is characterized by a variety of physical mechanisms
and types of instability.
There are various physical phenomena that can be the origin of a heat release on the
interface. For example, the interfacial heat release accompanies an interfacial chemical
reaction and the evaporation. It is known that the presence of a constant, spatially
uniform heat release or consumption at the interface can lead to the appearance of an
oscillatory instability.
In the present work, the influence of the interfacial heat release on nonlinear oscilla-
tory convective regimes, developed under the joint action of buoyant and thermocapillary
effects in the 47v2 silicone oil - water system, is studied. The system is bounded from
above and from below by two isothermal rigid plates kept at constant different tem-
peratures (the system is heated from below). It is assumed that the interfacial tension
decreases linearly with an increase of the temperature. A constant heat release is set on
the interface. The boundary-value problem is solved by the finite-difference method.
The wide range of the modified Grashof number values, corresponding to heat sources
and heat sinks at the interface, is considered. It is found that the presence of the inter-
facial heat release can change the sequence of bifurcations and lead to the appearance
of specific oscillatory regimes with different symmetry properties. It is shown that the
period of oscillations changes in a non-monotonic way for symmetric and asymmetric
oscillations. The region of nonlinear convective oscillations is observed in a finite interval
of the Grashof number values bounded from below and from above.

Abstract document

IAC-13,A2,4,5,x19746.brief.pdf

Manuscript document

IAC-13,A2,4,5,x19746.pdf (🔒 authorized access only).

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