Showing papers by "Manoochehr Koochesfahani published in 1979"
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TL;DR: In this article, the authors measured the strength and location of the vorticity center of the large structures in a two-dimensional shear layer using Laser Doppler velocimetry in the GALCIT free-surface water tunnel.
Abstract: Investigations into the nature of the large structures in a two-dimensional shear layer were carried out using
laser Doppler velocimetry in the GALCIT free-surface water tunnel. By simultaneous measurements of velocity
at two points outside the turbulent region, above and below the shear layer, it was possible to measure the
strength (total circulation) and location of the vorticity center of the large structures. It was found that structures
not in the process of pairing convect downstream with the center of their cores close to the ray y/x along which
the mean velocity is given by U_m = l/2(U_1 + U_1 ). The determined value of the mean circulation is consistent with
the independent measurements of the mean spacing between the structures. Results indicate that if the large
structure vorticity distribution is elliptical, the inclination angle of its axis of symmetry with respect to the now
direction is small.
26 citations