Magnetohydrodynamic flow around a sphere

The flow of an incompressible, viscous, electrically conducting fluid past a sphere in an aligned magnetic field is investigated using the finite difference method for Re 100 and 200 and interaction parameter N in the range 0⩽N⩽10 (or 0⩽M⩽100), where M is the Hartmann number defined by M=2NRe. The length of the recirculation bubble in the flow reduces monotonically with increasing magnetic field up to N=1 and starts growing when N⩾2. A non-monotonic behavior of the boundary layer separation angle is found when N<1, where the backward movement of the separation angle is observed. For higher values of N, a linear dependence with N of the pressure drag coefficient, the total drag coefficient and the rear pressure is found. With increasing values of N, a general increase in upstream base pressure and a decrease in downstream base pressure is noted. The features found in this work are in agreement with those of experimental findings.