INFLUENCE OF VARIABLE LIQUID PROPERTIES ON MAGNETOHYDRODYNAMIC FLOW AND HEAT TRANSFER OF A CASSON LIQUID OVER A SLENDER ROTATING DISK: NUMERICAL AND OPTIMAL SOLUTION

The present work deals with magnetohydrodynamic (MHD) flow and heat transfer of a Casson liquid over a rotating disk with variable thickness. The effects of velocity slip, convective boundary condition, viscous dissipation, and internal heat generation/absorption are considered. The transport properties of the fluid, for example, viscosity dissipation and thermal conductivity, vary with temperature. The governing nonlinear partial differential equations of the problem are reduced to a system of nonlinear ordinary differential equations by the von Karman approach and are solved numerically as well as semi-analytically. The numerical results are compared with previous studies for a special case and found to be in excellent agreement. Impacts of the pertinent parameters on the velocity components and the temperature field are graphically presented and analyzed in detail. The temperature distribution gets augmented for raising the values of viscous dissipation; variable thermal conductivity, and heat source/sink parameter.