Combined Effects of Frictional and Joule Heating on MHD Nonlinear Radiative Casson and Williamson Ferrofluid Flows with Temperature Dependent Viscosity

The impacts of Joule's dissipation and frictional heating on non-Newtonian ferrofluid flows past a bidirectionally stretching convective surface are investigated. We assumed that Fe₃O₄ nanoparticles are mixed with methanol. Both Casson and Williamson models are opted while formulating the basic flow equations. The impact of temperature dependent viscosity is accounted. The Joule heating and viscous dissipation impacts are also considered. Shooting and R.K. numerical procedures are used to solve the flow problem. Graphical and tabular illustrations are presented with a view of understanding the nature of flow and heat transfer for discrete values of flow parameters. It is worth to note that the thickness of velocity boundary layer of Casson fluid flow is greater than that of Williamson fluid flow. Also the presence of Joule and frictional heating leads to more heat energy to Casson fluid flow while compared to that of Williamson fluid. Heat transfer rate is better in Williamson fluid compared to that of Casson fluid.