The effect of magnetic field dependent (MFD) viscosity on thermal convection in a horizontal ferromagnetic fluid layer has been investigated numerically. A correction is applied to Sunil et al.  which is very important in order to predict the correct behavior of MFD viscosity. Linear stability analysis has been carried out for stationary convection. The MFD viscosity parameter δ as well as the measure of nonlinearity of magnetization M3, both have a stabilizing effect on the system. Numerical results are also obtained for large values of magnetic parameter M1 and predicted graphically.
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