Magnetoconvection in fluids with suspended particles under 1g and ?g
Magnetic field; Micropolar fluid; Rayleigh-Benard-Marangoni; Suspended particles; Suspensions
The role of magnetic field in the inhibition of natural convection driven by combined buoyancy and surface tension forces in a horizontal layer of an electrically conducting Boussinesq fluid with suspended particles confined between an upper free/adiabatic and a lower rigid/isothermal boundary is considered in 1g and ?g situations. The inhibition of convection is caused by a stationary and uniform magnetic field parallel to the gravity field. The magnetically-inert suspended particles are not directly influenced by the magnetic field but are influenced indirectly by the magnetically responding carrier fluid in which they are suspended. A linear stability analysis of the system is performed. The Rayleigh-Ritz technique is used to obtain the eigenvalues. The influence of various parameters on the onset of convection has been analysed. Six different reference steady-state temperature profiles are considered and their comparative influence on onset is discussed. Treating Marangoni number as the critical parameter it is shown that any particular infinitesimal disturbance can be stabilized with a sufficiently strong magnetic field. It is observed that the electrically conducting fluid layer with suspended particles heated from below is more stable compared to the classical electrically conducting fluid layer without suspended particles. The critical wave number is found to be insensitive to the changes in the suspension parameters but sensitive to the changes in the Chandrasekhar number. The problem has possible space applications. 2002 itions scientifiques et micales Elsevier SAS. All rights reserved.
Aerospace Science and Technology, Vol-6, No. 2, pp. 105-114.
Siddheshwar P.G., UGC-DSA Centre in Fluid Mechanics, Department of Mathematics, Bangalore University, Bangalore 560 001, India; Pranesh S., Department of Mathematics, Christ College, Bangalore 560 029, Hosur Road, India