Influence of cross-diffusion and radiation on mixed convection between rotating discs in the presence of a variable magnetic field

Abstract

Abstract.In the present article, Navier-Stokes equations along with heat/mass transfers are taken into account for the squeezing flow of a viscous fluid between two rotating and parallel discs. The flow is also under the influence of an external applied magnetic field, $ M^{f}$Mf, which will give rise to an induced magnetic field $ B(r, \\theta, z)$B(r,θ,z) with components $ B_{r}$Br, $ B_{\\theta}$Bθ and $ B_{z}$Bz between the two discs. A similarity solution is obtained through the homotopy analysis method (HAM) with appropriate initial guesses and the auxiliary parameter to produce an algorithm with an accelerated and assured convergence. An investigation is made for the effects of the rotational motions of two discs, upward/downward motion of an upper disc, magnetic force on velocity components, the pressure and the torques that the fluid exerts on the discs. Tabulated and graphical results show that an increase in the rotational Reynolds number increases the pressure, torque and azimuthal/axial components of the induced magnetic field. HAM results are compared with numerical results obtained by BVP4c to assure the accuracy of HAM. A parametric study is tabulated and discussed with graphical results.