Analytical Investigation of MHD Natural Convection Heat and Mass Transfer with Radially Varying Heat Absorption in a Vertical Concentric Annulus

Abstract

This study presents an analytical investigation of the combined effects of an applied radial magnetic field, an induced magnetic field, and inverse-square heat and mass absorption on fully developed natural convection flow of laminar, viscous incompressible electrically conducting fluid. The governing equations are formulated non-dimensionally and solved analytically under steady-state conditions. Key dimensionless parameters, such as the Hartmann number (Ha), heat absorption parameter (S), chemical reaction parameter (K*) and annular gap ratio (λ), are systematically varied to examine their effects on velocity, temperature, concentration, magnetic field, and induced current density distributions. The results indicate that increasing Hartmann number suppresses velocity due to Lorentz force effects while enhancing the magnetic field intensity. The annular gap ratio significantly influences flow characteristics, promoting enhanced heat and mass transfer. Higher heat absorption reduces velocity and temperature, confirming its role in energy extraction, while an increase in the chemical reaction parameter (K*) depletes concentration due to accelerated species diffusion. Furthermore, isothermal boundary conditions exhibit higher Nusselt and Sherwood numbers compared to iso-flux conditions, demonstrating improved convective transport. These findings provide critical insights into optimizing MHD-driven thermal and mass transport systems, with potential applications in nuclear reactor cooling, electromagnetic propulsion, and advanced energy conversion technologies.