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Intrinsic and extrinsic vortex nucleation mechanisms in the flow

F. V. Kusmartsev
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Abstract

We propose very general vortex nucleation mechanisms analogous to a hydrodynamic instability and calculate associated critical velocity in agreement with experiments. The creation of vortices via extrinsic mechanism is driven by a formation of the surface vorticity sheet created by the flow, which reaches a critical size. Such a sheet screens an attraction of a half-vortex ring to the wall, the barrier for the vortex nucleation disappears and the vortex nucleation is started. In the intrinsic mechanism the creation of a big vortex ring, which transforms into the vortex, is driven by a fluctuative generation of small vortex rings

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F. V. Kusmartsev. 1996-06-01. Intrinsic and extrinsic vortex nucleation mechanisms in the flow. https://doi.org/10.1007/bf02569431

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