High Stokes number wave focusing by a circular ridge: Internal, inertial and inertia-gravity waves

Abstract : We consider the focusing and breaking of internal waves generated by the horizontal oscillations of a very large torus mounted at the Coriolis platform, of 13 m diameter. The platform was filled with a linearly stratified fluid and rotated at a constant speed, or stood still to investigate, respectively, inertia-gravity or internal gravity waves. The wave field was measured using 2D or 3D PIV. The large torus size gives access to large Stokes numbers. Nonlinear effects and turbulence are observed in the focal region, but they can be described by linear theory with an eddy viscosity. Spectrum analysis shows the generation of higher harmonics in the focal zone even at low oscillation amplitude. The vertical vorticity field of internal gravity waves exhibits a dipolar structure in the focal zone, which transforms in the rotating case into a "Yin-Yang-shaped" structure. The overall structure of the inertial waves is close to that of internal gravity waves, though the overturning motion in the focal region is relatively intense.
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-01647853
Contributor : Jan-Bert Flor <>
Submitted on : Wednesday, November 28, 2018 - 9:29:57 AM
Last modification on : Thursday, January 3, 2019 - 4:30:09 PM

File

shmakova-natalia-article.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : hal-01647853, version 1

Collections

LEGI | UGA

Citation

Natalia Shmakova, Jan-Bert Flór, Bruno Voisin, Joël Sommeria, Samuel Viboud. High Stokes number wave focusing by a circular ridge: Internal, inertial and inertia-gravity waves. VIIIth International Symposium on Stratified Flows, Aug 2016, San Diego, United States. ⟨hal-01647853⟩

Share

Metrics

Record views

100

Files downloads

10