Natural convection of liquid metal in a horizontal cylindrical annulus under radial magnetic field

In this article, the effect of a radial magnetic field on the steady, laminar and natural convection flow of molten potassium in a long horizontal annulus between two horizontal cylinders is investigated numerically. The inner and outer cylinders are at T-H and T-C temperatures, respectively, with T-H > T-C. A finite volume code based on SIMPLER-algorithm is used to solve the governing equations of the model. Simulations are carried out for a wide range of the Rayleigh number (Ra), Hartmann number (Ha) and radii ratio (lambda). It is shown that for a given radii ratio as the strength of magnetic field increases, the convection heat transfer reduces. For narrow annulus, the effect of Hartmann number on the maximum absolute value of the stream function is not eminent compared to the case of high radii ratio. Furthermore it is found that for a given Ha and Ra, the average Nusselt number increases up to about lambda = 5 and then reduces gently as lambda enhances. Moreover, for all Hartmann numbers the effect of radii ratio on the average Nusselt number has almost the same trend.