MAGNETIC AND GRAVITATIONAL CONVECTION OF AIR WITH A COIL INCLINED AROUND THE X AXIS

Abstract

Air is filled in a cubic enclosure whose one vertical wall is isothermally heated and the opposite one is cooled while the other four walls are thermally insulated. A large coil is placed outside of this enclosure with the coil center coinciding with the cube center. An electric current in the coil generates a magnetic field to affect the convection of air, because the air contains oxygen whose magnetic susceptibility is exceptionally large among gases. The coil is further inclined around the X axis, which is horizontal and perpendicular to the hot and cold walls through the wall center. The heat transfer rate changes depending on the inclination angle. This system is studied numerically for convection for the following combination of parameters: Ra = 1.51 × 10⁴, 9.06 × 10⁴; Pr = 0.71; γ = 0 − 100; x_Euler = 0–π/2, where γ represents the strength of magnetic field and x_Euler is the angle of inclination of the coil. For example, at Ra = 1.51 × 10⁴ and γ = 30, the average Nusselt number 2.535 at x_Euler = 0 increased to 2.823 at x_Euler = π/2. This study suggests that the coil inclination affects the heat transfer rate extensively.