2012/03/31 by Guilhem Bordes, Antoine Venaille, Sylvain Joubaud +2
Earth and Planetary Sciences · Physics and Astronomy · #Amplitude #Gravity wave #Internal wave #Jet (fluid) #Mean flow #Ocean Waves and Remote Sensing #Oceanographic and Atmospheric Processes #Reynolds number #Stratified flow #Stratified flows #Tropical and Extratropical Cyclones Research #Vorticity #Wave propagation #physics.ao-ph #physics.flu-dyn
paper · pdf · doi:10.1063/1.4745880
published as Physics of Fluids 24, 8 (2012) 086602
openalex publication_date 2012/08/01 · arxiv created 2012/08/31 · arxiv updated 2012/09/03 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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. Using multiple scale analysis, 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. These results show that a mean flow with non-zero vertical vorticity can be generated by Reynolds stresses if the wave fulfils two conditions: (1) the wave amplitude must vary along its propagation direction, which is the case in the presence of viscosity; (2) the wave amplitude must vary in the lateral direction, which is the case when the wave generator is localized in space.