Instability in electromagnetically driven flows. II
- Imazio, Paola Rodriguez and Gissinger, ChristophePHYSICS OF FLUIDS 28
Abstract : In a previous paper, we have reported numerical simulations of the
magnetohydrodynamic flow driven by a travelling magnetic field in an
annular channel, at low Reynolds number. It was shown that the stalling
of such induction pump is strongly related to magnetic flux expulsion.
In the present article, we show that for larger hydrodynamic Reynolds
number, and with more realistic boundary conditions, this instability
takes the form of a large axisymmetric vortex flow in the (r, z)-plane,
in which the fluid is locally pumped in the direction opposite to the
one of the magnetic field. Close to the marginal stability of this
vortex flow, a low-frequency pulsation is generated. Finally, these
results are compared to theoretical predictions and are discussed within
the framework of experimental annular linear induction electromagnetic
pumps. (C) 2016 AIP Publishing LLC.