Analysis of the influence of a strong magnetic field gradient on convection process of paramagnetic fluid in the annulus between horizontal concentric cylinders

Abstract

The paper presents findings of analysis of the effect of a strong magnetic field gradient on the natural thermal convection of paramagnetic fluid. The study have been done in a 3D annulus between horizontal coaxial concentric cylinders filled with paramagnetic fluid. The inner cylindrical surface was heated and the outer cylindrical surface was cooled. Measuring vessel has been placed in a magnetic field gradient inside the superconductive magnet. The research has been divided into two parts in order to validate theoretical model. In the experimental part: an impact analysis of a strong magnetic field on value of the Nusselt number for three various configurations of the magnetic field relative to the gravitational field was carried out. The value of Rayleigh number was approximately Ra = 1.5•105. In the numerical part: the forces acting on electrically non-conductive, paramagnetic fluid situated in a gravitational field and a strong inhomogeneous magnetic field exposed to the temperature difference were described. The result showed that high magnetic field can be used to either enhance or suppress thermal convection of paramagnetic fluid.