The onset of ferromagnetic convection
in a micropolar ferromagnetic fluid layer heated from below in the presence of
a uniform applied vertical magnetic field has been investigated. The
rigid-isothermal boundaries of the fluid layer are considered to be either
paramagnetic or ferromagnetic and the eigenvalue problem is solved numerically
using the Galerkin method. It is noted that the paramagnetic boundaries with
large magnetic susceptibilityχdelays the onset
of ferromagnetic convection the most when compared to very low magnetic
susceptibility as well as ferromagnetic boundaries. Increase in the value of
magnetic parameterM1and spin diffusion (couple stress) parameter N3 is to hasten, while increase in the value of
coupling parameterN1 and micropolar heat conduction parameter N5 is to delay the onset of ferromagnetic
convection. Further, increase in the value ofM1, N1,N5 andχas well as decrease
in N3 is to diminish the size of convection cells.
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