Direct measurement of hairpin-like vortices in the bottom boundary layer of the coastal ocean
- Steele, ECC
- Nimmo-Smith, WAM
- Vlasenko, A
DOIAbstract
Laboratory measurements and numerical modeling at low Reynolds numbers (Reθ<7700) indicate the energy-containing turbulence of boundary layer flows comprises coherent packets of hairpin vortices. Here direct measurements in the bottom boundary layer of the coastal ocean at higher Reynolds numbers (Reθ = 266,150) show tidal flows also contain packets of large vortices separated by periods of more quiescent conditions. The 1452 vortices recorded within a 20 min period are typically aligned along stream (∼8.0° from the mean flow direction) and inclined to the horizontal (∼27.0° from the seabed), with a mean period of occurrence of 4.3 s. These results lend three-dimensional, in situ support to an interpretation of the coastal ocean bottom boun...
Add to ORKG