Strongly nonlinear steepening of long interfacial waves
- 1Département de Physique, Université des Antilles et de la Guyane, Guadeloupe, France
- 2Department of Nonlinear Geophysical Processes, Institute of Applied Physics, Nizhny Novgorod, Russia
- 3Department of Applied Mathematics, Nizhny Novgorod Technical State University, Nizhny Novgorod, Russia
Abstract. The transformation of nonlinear long internal waves in a two-layer fluid is studied in the Boussinesq and rigid-lid approximation. Explicit analytic formulation of the evolution equation in terms of the Riemann invariants allows us to obtain analytical results characterizing strongly nonlinear wave steepening, including the spectral evolution. Effects manifesting the action of high nonlinear corrections of the model are highlighted. It is shown, in particular, that the breaking points on the wave profile may shift from the zero-crossing level. The wave steepening happens in a different way if the density jump is placed near the middle of the water bulk: then the wave deformation is almost symmetrical and two phases appear where the wave breaks.