| Autor: |
Roach AH; Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas and Princeton Plasma Physics Laboratory, P.O. Box 451 Princeton, New Jersey 08543, USA. aroach@pppl.gov, Spence EJ, Gissinger C, Edlund EM, Sloboda P, Goodman J, Ji H |
| Jazyk: |
angličtina |
| Zdroj: |
Physical review letters [Phys Rev Lett] 2012 Apr 13; Vol. 108 (15), pp. 154502. Date of Electronic Publication: 2012 Apr 11. |
| DOI: |
10.1103/PhysRevLett.108.154502 |
| Abstrakt: |
We report on observations of a free-Shercliff-layer instability in a Taylor-Couette experiment using a liquid metal over a wide range of Reynolds numbers, Re∼10(3)-10(6). The free Shercliff layer is formed by imposing a sufficiently strong axial magnetic field across a pair of differentially rotating axial end cap rings. This layer is destabilized by a hydrodynamic Kelvin-Helmholtz-type instability, characterized by velocity fluctuations in the r-θ plane. The instability appears with an Elsasser number above unity, and saturates with an azimuthal mode number m which increases with the Elsasser number. Measurements of the structure agree well with 2D global linear mode analyses and 3D global nonlinear simulations. These observations have implications for a range of rotating MHD systems in which similar shear layers may be produced. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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