Wave resonant interactions constitute an efficient mechanism to exchange energy between nonlinear waves. Although these interactions are the fundamental ingredient of wave turbulence, only few experiments exist in the case of gravity surface waves.

I will talk about experiments on resonant interactions among gravity surface waves in a large basin. Two crossing sinusoidal waves interact nonlinearly to give birth to a resonant wave whose properties are fully characterized, and compared to the weakly nonlinear wave interaction theory. I will also discuss results of experiments for stronger nonlinear waves or for off-resonance conditions.

This work has been funded by ANR Turbulon, and performed in collaboration with F. Bonnefoy (EC Nantes), G. Michel, B. Semin (ENS Paris), S. Aumaître, T. Humbert, (CEA Saclay), M. Berhanu and F. Haudin (MSC Paris)