Experimental observation of a strong mean flow induced by internal gravity waves

Guilhem Bordes (1) , Antoine Venaille (1) , Sylvain Joubaud (1) , Philippe Odier (1) , Thierry Dauxois (1)

1 Phys-ENS - Laboratoire de Physique de l'ENS Lyon

We report the experimental observation of a robust horizontal mean flow induced by internal gravity waves. A wave beam is forced at the lateral boundary of a tank filled with a linearly stratified fluid initially at rest. After a transient regime, a strong jet appears in the wave beam, with horizontal recirculations outside the wave beam. We present a simple physical mechanism predicting the growth rate of the mean flow and its initial spatial structure. We find good agreement with experimental results.

Mots clés: internal gravity waves; wave-mean flow interactions; stratified fluids; jet; vortex; wave propagation; viscous flows

Domaines: Dynamique des Fluides [physics.flu-dyn]; Physique Atmosphérique et Océanique [physics.ao-ph]

Guilhem Bordes, Antoine Venaille, Sylvain Joubaud, Philippe Odier, Thierry Dauxois. Experimental observation of a strong mean flow induced by internal gravity waves. Physics of Fluids, 2012, 24 (8), pp.086602. ⟨10.1063/1.4745880⟩. ⟨hal-00678777v3⟩