EXPERIMENTAL STUDY OF PARAMETRIC OSCILLATIONS OF INTERFACE BETWEEN TWO IMMISCIBLE LIQUIDS IN A CONICAL THIN LAYER

The stability of an oscillating interface between two immiscible low-viscosity liquids of different densities in a thin layer formed by two conical surfaces is experimentally studied. The symmetry axis of the cuvette is oriented along the gravity field. The oscillations of the liquids are set by a hydraulic pump to which the upper and lower outlets of the layer are connected. It is found that with an increase in the oscillation amplitude, parametric instability of the interface in the form of a standing azimuthal-periodic wave is excited. Analysis of the dispersion relation shows that the waves have a gravitational-capillary nature. The instability thresholds and supercritical wave dynamics are investigated and analyzed depending on the oscillation parameters and properties of liquids.