| Popis: |
We consider the influence of a rotating magnetic field on an infinitely long cylindrical liquid metal column. A solution for the flow field and magnetic field distribution is obtained for any value of the Hartmann number, Ha, and of the shielding parameter, Rω. When Ha ⪢ 1, it has been shown that, as long as R ω Ha √2 , the flow consists of a core rotating with the same angular velocity as that of the magnetic field and of a Hartmann boundary layer at the wall. The flow also contains recirculating eddies which are aligned with the magnetic field in the cylinder core. It is noted that the magnetic field is swept by the convective effect of the flow in the wall boundary layer whereas it satisfies a pure diffusion regime in the core. A simplified ring model permits a simple explanation of the critical value R ω = Ha √2 . |
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