%0 Journal Article %A Prakash, Jyoti %A Manan, Shweta %A Kumar, Pankaj %D 2018 %I Begell House %K ferrofluid, convection, porous medium, magnetic field dependent viscosity %N 8 %P 749-762 %R 10.1615/JPorMedia.2018018832 %T FERROMAGNETIC CONVECTION IN A SPARSELY DISTRIBUTED POROUS MEDIUM WITH MAGNETIC FIELD DEPENDENT VISCOSITY REVISITED %U https://www.dl.begellhouse.com/journals/49dcde6d4c0809db,34750f7b6e4fb637,217b56181a41520b.html %V 21 %X The effect of magnetic field dependent (MFD) viscosity on the thermal convection in a ferromagnetic fluid in the presence of a uniform vertical magnetic field has been studied for a fluid layer saturating a sparsely distributed porous medium by using the Darcy-Brinkman model. A correction is applied to Vaidyanathan et al. (Ind. J. Pure Appl. Phys., 40(3), (2002), 166) which is very important in order to predict the correct behavior of MFD viscosity. A linear stability analysis has been carried out for stationary modes. The critical wave number and critical Rayleigh number for the onset of instability, for the case of free boundaries, are determined numerically for sufficiently large values of the magnetic parameter M1. Numerical results are obtained and are illustrated graphically. It is shown that magnetic field dependent viscosity has a stabilizing effect on the system, whereas medium permeability has a destabilizing effect. %8 2018-07-16