Sergey Prants

43, Baltiyskaya Street, Vladivostok, 690041, Russia
V.I. Il'ichev Pacific Oceanological Institute of the Far-Eastern Branch of RAS
Publications:
Wang W., Prants S. V., Zhang J., Wang L.
A Lagrangian Analysis of Vortex Formation in the Wake behind a Transversely Oscillating Cylinder
2018, vol. 23, no. 5, pp. 583-594
Abstract
A vortex pair+single vortex (P+S) wake behind a transversely oscillating cylinder
is investigated from the Lagrangian point of view. The Lagrangian coherent structures (LCSs) of
the flow are computed to analyze formation of vortices in the wake. An asymmetric vortex street
is obtained by using a dynamic mesh method. The corresponding vorticity field is found to agree
well with real experiments. The LCSs are approximated by ridges of the finite-time Lyapunov
exponents computed from transient velocity fields. The formation process is investigated using
the vorticity field and the LCSs. It is found that details of the wake pattern are sensitive to
initial oscillation conditions, and that the cylinder motion causes an early roll-up of boundary
layers to form new vortex structures in the wake. Lagrangian description of the flow with the
help of the LCSs provides further details about formation of vortices in the cylinder flow and
helps to get a new insight into the flow structure in the wake region.
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Prants S. V.
A Lagrangian Study of Eddies in the Ocean
2016, vol. 21, no. 3, pp. 335-350
Abstract
A brief review of our results on the application of the Lagrangian approach to study observed and simulated eddies in the ocean is presented. It is shown by a few examples of mesoscale vortex structures in the North Western Pacific how to compute and analyze maps of specific Lagrangian indicators in order to study the birth, formation, evolution, metamorphoses and death of ocean eddies. The examples involve two-dimensional eddies observed in satellitederived velocity fields in the deep ocean and three-dimensional ones simulated in a regional numerical model of circulation with a high resolution.
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