Hydromagnetic effects on steady flow of Casson nanofluid through rotating co-axial cylinders

In the proposed mathematical model, we have examined hydromagnetic effects on the steady flow of Casson nanofluid through two co-axial horizontal rotating cylinders. The inner and outer cylinders are revolving about their axes with different angular velocity. Using Schauder's fixed point theorem, the existence of a solution to the differential equation has been demonstrated. The expression for the velocity profile involves the modified Bessel functions of first and second kinds. Special cases on velocity profile are obtained for the limiting value of permeability parameter, Casson parameter, Hartmann number, and ratio of angular velocity, respectively. Graphs of velocity profile are plotted for different values of permeability parameter, Casson parameter, aspect ratio, Hartmann number, ratio of angular velocity, and their graphical behaviors are also discussed. It is observed from graphical data that the velocity of Casson nanofluid increases when the permeability parameter, the aspect ratio of radii, or the ratio of angular velocity increases and decreases when either the Casson fluid parameter or the Hartmann number increases.