Abstract: An exact solution for the hydromagnetic flow past
an accelerated horizontal infinite porous plate in the presence of Hall effect
is presented. The fluid initially rotates with uniform angular velocity about an
axis normal to the plate in unison with the plate when the fluid is permeated by
a transverse magnetic field and the Hall effect is taken into account. Effects
of m, M,
W on the velocity profiles are presented
graphically for both suction and injection while the values of skin-friction
are presented in tables. Here, m and M represent the Hall
parameter, magnetic field parameter, respectively and W is
the angular velocity about which the plate rotates in unison with the fluid
about an axis normal to the plate. It is found that, at a given instant the
velocity component (axial velocity) along the direction of motion of the plate
increases while the transverse velocity (transverse to the main flow) component
decreases for an increase in the rotation parameter in the cases of both suction
and injection. Due to application of both suction and injection, an increase in m
(M) leads to an increase (decrease) in the axial velocity while the
transverse velocity increases for both m
and M. Also, an increase in suction
(injection) leads to a decrease (increase) in axial velocity, while the
transverse velocity decreases in both cases of suction and injection. Further,
for both suction and injection an increase in m (M) shows decreasing (increasing) behaviour in axial
skin-friction and increasing (decreasing) in the transverse skin-friction. For
fixed magnetic, Hall and rotation parameter an increasing in suction (injection)
give rise to an increase (decrease) in axial skin-friction, while the transverse
skin-friction decreases for both suction and injection.
Keywords and phrases: Hall effect, unsteady flow, rotating flow, accelerated plate.
