Three-dimensional, time-resolved velocity and density measurements of the stratified shear flow in an inclined duct

Abstract

Laboratory experiments on the stratified shear flow in an inclined duct are reported. Stratified turbulence is observed in this two-layer exchange flow, whose dissipation is controlled by the duct inclination and compares in intensity with that observed in geo- physical contexts. A setup enabling three-dimensional (3D) simultaneous Particle Image Velocimetry (PIV) and Laser-Induced Fluorescence (LIF) is presented, and applied to the visualisation of Holmboe waves. Such capabilities are believed to be key to advance our understanding of the dynamics and mixing of stratified turbulence in the near future.