Abstract:
In our study we have investigated hydromagnetic unsteady flow of a viscous
incompressible fluid between two flat, parallel porous semi-infinite plates with constant
suction in the presence of a transverse variable magnetic field. The flow variables such as
velocity and thermodynamic properties at every point in the fluid vary with respect to
time. The fluid is assumed to be flowing in the positive x direction between two parallel
flat plates located at the y = ± L planes. We have particularly investigated the effects of
Suction (V0), Hydrodynamic Reynolds number (Re), magnetic pressure number (Rh),
Eckert number (Ec), Prandtl number (Pr), Variable magnetic field gradient (Fgrand) and
magnetic field intensity (B) normal to the direction of flow on the dynamic behavior of the
fluid when the lower plate is impulsively started in x direction at constant velocity U,
while the upper plate remains stationary. We have employed the finite difference method
to solve the coupled non-linear and dimensionless partial differential equations governing
this problem. The iterations were performed using a computer program and the results
have been presented graphically. Our findings show that both primary and secondary
velocity profiles are largely influenced by change in V0, Re, Rh, By, and Fgrand.
Temperature profiles are unaffected by magnetic field intensity (By) but influenced by
suction, Prandtl number and Eckert number.
