2006/03/23 by Louis Gostiaux, Thierry Dauxois, Henri Didelle +3 · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Oceanographic and Atmospheric Processes #Seismic Imaging and Inversion Techniques #Seismic Waves and Analysis #nlin.PS #physics.flu-dyn
paper · pdf · doi:10.1063/1.2197528
published as Physics of Fluids 18 (2006) 056602
arxiv created 2006/03/23 · openalex publication_date 2006/05/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Internal waves propagate obliquely through a stratified fluid with an angle that is fixed with respect to gravity. Upon reflection on a sloping bed, striking phenomena are expected to occur close to the slope. We present here laboratory observations at moderately large Reynolds number. A particle image velocimetry technique is used to provide time-resolved velocity fields in large volumes. Generation of the second and third harmonic frequencies is clearly demonstrated in the impact zone. The mechanism for nonlinear wavelength selection is also discussed. Evanescent waves with frequency larger than the Brunt-Väisälä frequency are detected and experimental results agree very well with theoretical predictions. The amplitude of the different harmonics after reflection is also obtained.