Satyanarayana Badeti
VIT - AP University, India
Title: The modification of Ekman-Hartmann layer by the imposition of axial velocity
Biography
Biography: Satyanarayana Badeti
Abstract
The effect of normal blowing on a linear, steady, axisymmetric Ekman-Hartmann boundary layer on an infinite flat insulating plate is analyzed. The problem is governed by three parameters, namely the Ekman number
, the magnetic interaction parameter
and the injection Rossby number
. In the parametric range
and
, the viscous Ekman-Hartmann layer is blown up by the injection of the fluid, and it becomes inviscid to the lowest order. Injection and magnetic terms balance each other giving rise to a new boundary layer of thickness
, which may be called linear resistive layer. Since, the resistive layer is thicker than the Ekman-Hartmann layer, it can support more electric and mass flux, thus signifying a possible faster spin-up compared to conventional hydromagnetic case. The electric current increases with magnetic interaction parameter α beyond the saturation value, and finally approaches the saturation value as
. The vertical mass flux into the resistive layer decreases with magnetic field as expected because of the stiffening effect of the magnetic field. This resistive layer, characterized by dispersive and diffusive length scales for
merges with the interior and becomes a resistive region in the parameter range
and
. The other parameter ranges are clearly identified wherein the resistive
layer merges smoothly into the Ekman layer, the
injection layer that occurs when
, the Ekman-Hartmann layer and the
Hartmann layer. In addition to exact solutions, asymptotic solutions are also given for 
andto understand the problem more systematically and physically.