Breakdown of parametric fluid oscillations

Under the conditions of Faraday resonance the breakdown of oscillations of the free surface of a homogeneous fluid and of the interface in a two-layer fluid in a rectangular vessel is investigated. Experimentally, for several modes of surface and internal waves, the breakdown frequencies are measured and it is observed that on approaching these frequencies the waves intensely disintegrate. As in the theory of parametric oscillations of mechanical systems with one degree of freedom, the theoretical modeling is based on the assumption of the determining role of dissipative factors. For breaking Faraday waves an equivalent damping coefficient is introduced and estimated from experimental resonance curves. The applicability of the approach proposed is demonstrated with reference to a mechanical system with one degree of freedom: a physical pendulum with the suspension point oscillating vertically.