Wave turbulence on the surface of a fluid
CNRS - Paris Diderot University
Mon, Dec. 09th 2013, 14:00-15:00
Salle Claude Itzykson, Bât. 774, Orme des Merisiers
When waves of large enough amplitudes propagate within a dispersive medium, they interact nonlinearly with each other to generate waves at different wavelengths. This energy transfer from large scales (where the energy is injected) to small scales (where it is dissipated) is called wave turbulence. This cascade phenomenology presents analogies with hydrodynamical turbulence and occurs in all fields of physics involving wave dynamics: oceanic surface waves, internal waves in geophysics, Alfven waves in astrophysical plasmas, or spin waves in solid state physics. Although the theory of wave turbulence predicts out-of-equilibrium stationary solutions of the wave field statistics since the 1960's, well-controlled laboratory experiments on wave turbulence are relatively scarce despite the experimental efforts of the last decade. par I shall speak about experiments on gravity-capillary wave turbulence on the surface of a fluid using full resolved space-time measurements of the wave field. Their dynamical and statistical properties are then compared to wave turbulence theory. We notably underline that the existence of strong nonlinear waves, coherent structures, and dissipation occurring at all scales should be included in the theory to better describe the experimental results.