First report of the MILESTONE experiment: strongly stratified turbulence and mixing efficiency in the Coriolis platform

Antoine Campagne (1) , Henrik Alfredsson (2) , Rémi Chassagne (1) , Diane Micard (3) , Nicolas Mordant (1) , Antonio Segalini (2) , Joël Sommeria (1) , Samuel Viboud (1) , Ashwin Vishnu Mohanan (2) , Erik Lindborg (2) , Pierre Augier (1)

1 LEGI - Laboratoire des Écoulements Géophysiques et Industriels [Grenoble]
2 Department of Mechanics [Stockholm]
3 LMFA - Laboratoire de Mecanique des Fluides et d'Acoustique

Strongly stratified turbulence is a possible interpretation of oceanic and atmospheric measurements. However, this regime has never been produced in a laboratory experiment because of the two conditions of very small horizontal Froude number F h and large buoyancy Reynolds number R which require a verily large experimental facility. We present a new attempt to study strongly stratified turbulence experimentally in the Coriolis platform. The flow is forced by a slow periodic movement of an array of six vertical cylinders of 25 cm diameter with a mesh of 75 cm. Five cameras are used for 3D-2C scanned horizontal particles image velocimetry (PIV) and stereo 2D vertical PIV. Five density-temperature probes are used to measure vertical and horizontal profiles and signals at fixed positions. The first preliminary results indicate that we manage to produce strongly stratified turbulence at very small F h and large R in a laboratory experiment.

Domaines: Dynamique des Fluides [physics.flu-dyn]

Antoine Campagne, Henrik Alfredsson, Rémi Chassagne, Diane Micard, Nicolas Mordant, et al.. First report of the MILESTONE experiment: strongly stratified turbulence and mixing efficiency in the Coriolis platform. VIIIth International Symposium on Stratified Flows (ISSF), Aug 2016, San Diego, United States. ⟨hal-01393325⟩