Thin layer effects in a stability problem for equilibrium states between liquid and vapor

L.G. Badratinova

Preprint No. 26, University of Freiburg, 1998, 32 p.

Language english [download]

The linear nonoscillatory stability of horizontal vapor layer resting g on a heated plate below a layer of its liquid is studied. The liquid is bounded above by a rigid plate that is colder than the low wall. At the plates, either a heat flux or a temperature is kept constant. The phases are assumed to be incompressible fluids with different physical properties. At their interface, phase change is introduced by perturbations; gravity and capillary effects are taken into account. Exact neutral stability conditions are derived, and are examined numerically and in the long-wave approximation. The results show that the arrangement can be linearly stable to nonoscillatory perturbations when both phases are in thin layers. The mechanism of stabilization is described. The stability conditions are formulated in terms of the thickness of the layers and some characteristic length scales.