Intrinsic and extrinsic vortex nucleation mechanisms in the flow
Abstract
We propose very general vortex nucleation mechanisms[1] 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.
- Publication:
-
Czechoslovak Journal of Physics Supplement
- Pub Date:
- January 1996
- DOI:
- 10.1007/BF02569431
- arXiv:
- arXiv:cond-mat/9605201
- Bibcode:
- 1996CzJPS..46...31K
- Keywords:
-
- Vortex;
- Vorticity;
- Vortex Ring;
- Critical Velocity;
- Hydrodynamic Instability;
- Condensed Matter
- E-Print:
- Contribution paper to LT21 (to be published in Physica B)