Abstract
Careful exploitation of the anisotropy native to late time stratified and rotating flows permits the use of a laser scanning measurement technique to simultaneously resolve the 2D velocity field in O(100) slices. The technique relies on getting the Reynolds number from the length scale while keeping the velocity small, this provides a characteristic time scale that is sufficiently large to permit full 3D scanning through the measurement volume in a relatively short time. As the vertical velocity component of these late time stratified flows is effectively zero, all components of the deformation tensor are resolved. 3D, time resolved measurements of the vorticity and enstrophy fields associated with stratified rotating flows such as vortex dipoles, monopoles and wakes are presented.
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Adam Fincham: He received his Ph.D. in Aerospace Engineering (Geophysical Fluid Dynamics) in 1994 from the University of Southern California. He worked as Chargé de Recherche for the CNRS at LEGI, Universite Joseph-Fourier, Grenoble, France from 1995-2004, where he performed experiments on the large rotating platform, Coriolis. He currently works at the University of Southern California Department of Aerospace and Mechanical Engineering as an Associate Research Professor. His current research interests include, turbulence and vortex structures in stratified and/or rotating flows, advanced algorithms for DPIV, 3D Scanning Imaging Velocimetry, particle dynamics in turbulent flows with application to oceanic planktonic ecosystems and sonic boom interactions with the ocean surface.