Hall effects on unsteady hydromagnetic flow induced by an eccentric–concentric rotation of a disk and a fluid at infinity

Abstract

The unsteady hydromagnetic flow of a viscous incompressible electrically conducting fluid induced by a sudden coincidence of two axes of rotation while a disk and the fluid at infinity are initially rotating with the same angular velocity about non-coincident axes in the presence of an axial uniform magnetic field has been examined considering the Hall effects. An exact solution of the governing equations has been obtained by the Laplace transform technique. The asymptotic behavior of the flow has been analyzed for small as well as large times to highlight transient approach to the steady state flow. It is found that the velocity components increase with an increase in Hall parameter. It is also found that for large time the steady state is reached through inertial oscillations. It is found that the solution for small values of time converges more rapidly than the general solution.Ó 2014 Production and hosting by Elsevier B.V. on behalf of Ain Shams University.

Exact solutions for unsteady free convection flow over an oscillating plate due to non-coaxial rotation

“…In subsequent investigations, Das et al. (2012) and Das and Jana (2014) used the same methodology and analyzed the effect of Hall current on MHD flow in a non-coaxial rotating frame. They found that both primary and secondary velocities were increasing when the value of the Hall parameter was increased.…”

Unsteady MHD flow due to eccentric rotations of a porous disk and an oscillating fluid at infinity

“…Das et al [16] presented the steady flow under the influence of Hall currents and slip condition. Das and Jana [17] considered the Hall effects on unsteady hydromagnetic flow by taking the eccentric-concentric rotation. Modather et al [18] conducted an analytical study to examine the effects of MHD heat and mass transfer on the oscillatory flow of a micropolar fluid.…”