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Vol.4 , No. 1, Publication Date: Feb. 27, 2018, Page: 15-26
 viscosity and non-uniform basic temperature profiles on the onset of thermomagnetic convection in a horizontal ferrofluid layer is studied analytically using linear stability theory, The lower and upper boundaries of the ferrofluid layer are assumed to be rigid by prescribing uniform heat flux condition at the lower boundary and a general thermal condition at the upper boundary. The Galerkin technique is used to find the eigenvalues as this technique is found to be more convenient to tackle different forms of basic temperature profiles. The results indicate that the basic cubic temperature profiles have a profound influence on the stability characteristics of the system and can be effectively used to either suppress or augment the onset of thermomagnetic convection. Results show that the conductive effect of non-steady conditions within the fluid layer does play a stabilizing state. It is observed that the effect of magnetic number, nonlinearity of the fluid magnetization is to hasten, while an increase in the magnetic field dependent viscosity parameter and Biot number is to delay the onset of ferroconvection.&picture=http://www.aascit.org/aascit/decorators/img/journal/928.jpg)
| [1] | Haligondanahally Nagendrappa Prakasha, Department of Mathematics, Akshaya Institue of Technology, Tumakuru, India. |
The combined effect of magnetic field dependent (MFD) viscosity and non-uniform basic temperature profiles on the onset of thermomagnetic convection in a horizontal ferrofluid layer is studied analytically using linear stability theory, The lower and upper boundaries of the ferrofluid layer are assumed to be rigid by prescribing uniform heat flux condition at the lower boundary and a general thermal condition at the upper boundary. The Galerkin technique is used to find the eigenvalues as this technique is found to be more convenient to tackle different forms of basic temperature profiles. The results indicate that the basic cubic temperature profiles have a profound influence on the stability characteristics of the system and can be effectively used to either suppress or augment the onset of thermomagnetic convection. Results show that the conductive effect of non-steady conditions within the fluid layer does play a stabilizing state. It is observed that the effect of magnetic number, nonlinearity of the fluid magnetization is to hasten, while an increase in the magnetic field dependent viscosity parameter and Biot number is to delay the onset of ferroconvection.
Keywords
Non-Uniform-Basic-Temperature Profiles, Ferroconvection, Magnetic-Fiield-Density Viscosity, Galerkin Technique, Darcy-Rayleigh Number, General Thermal Boundaries
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