Magnetohydrodynamic Carreau–Yasuda fluid with variable thermal conductivity and activation energy over a thermally radiated stretching cylinder

The magnetohydrodynamic flow and heat transfer of a Carreau–Yasuda fluid across a stretching cylinder are examined in this research, with variable thermal conductivity, thermal radiation, viscous dissipation, activation energy, and heat generation/absorption taken into account. A numerical simulation examining variable thermal properties and heat and mass transfer in 2D MHD Carreau-Yasuda fluid flow over an expanding cylinder under the influence of heat and mass transfer effects is an entirely novel concept in rheological studies, exploring the behaviors of such flows and not yet explored in available research. Employing the proper similarity transformations, the governing PDEs are converted into dimensionless form. Through the use of the MATLAB Bvp4c approach, ordinary differential equations are solved, yielding both numerical and graphical results. Graphical results are presented to show the impact of important physical parameters on velocity, temperature, and concentration profiles. It is found that dimensionless velocity, temperature and concentration profiles increase when the curvature parameter is enhanced. Furthermore, it is also observed that the temperature profile is enhanced for augmented values of the thermal conductivity parameter, radiation parameter, heat source, magnetic field parameter due to Joule dissipation and Eckert number, whereas the opposite trend is observed for the Prandtl number. The magnitude of the surface drag force (skin friction) decreases with the thermal and mass Grashof numbers, while the opposite trend is observed for the curvature parameter and magnetic field parameter. The concentration profile was enhanced for activation energy and a small diffusivity parameter. The surface drag force (skin friction) decreases with the thermal and mass Grashof numbers, and the opposite tendency is observed for the Curvature number and magnetic field parameter. The outcomes obtained are compared to previous findings that address certain limiting cases of the problem and were found to be in good agreement.