The numerical analysis on the variation of electric potential, electric current and Lorentz force with its influence on buoyancy-driven conjugate heat transfer and fluid flow using OpenFOAM

Highlights: • The variation of electric potential, electric current and Lorentz force is investigated in the domain under the influence of the magnetic field. • The influence of imposed magnetic field and its orientation on the electric current and Lorentz force is observed in the enclosure. • The Bx and By magnetic field induces dissimilar distribution of electric potential and hence, the electric current in the enclosure. • The low intensity of the magnetic field (Ha ≤ 25) synchronized the flow and regulated the heat transfer. -- Abstract: The development of electric potential, electric current and Lorentz force in the presence of the magnetic field in the fluid/solid domain is studied numerically. Moreover, the significance of the magnetic field and its orientation on the pattern of electric potential, electric current and the direction of the Lorentz force is observed in the enclosure. The buoyancy-driven conjugate heat transfer and fluid flow solver with Magnetohydrodynamics (MHD) is developed in open source CFD tool OpenFOAM. The buoyancy force in the enclosure is altered by varying the Rayleigh number of Ra = 10⁴, 10⁵, 10⁶, at the fixed Prandtl number of Pr = 0.02. The magnetic field is imposed in the x-direction (B_x) and y-direction (B_y) measured by Hartmann number of Ha = 0–100. The conjugate thermal and electromagnetic coupling is considered for the fluid-wall interface in the present analysis and includes the wall thickness within the computational domain. The orientation of the magnetic field shows the asymmetric (for B_x) and symmetric pattern (for B_y) of an electric potential distribution in the enclosure, and hence electric current. The detailed analysis of temperature iso-surface, isotherms, streamlines, and Nusselt number variations, etc in the presence of magnetic field are discussed in detail.