Comparative analysis on magnetohydrodynamic flow of non-Newtonian hybrid nanofluid over a stretching cylinder: Entropy generation

Abstract

This research examines the MHD boundary layer phenomenon of Casson and Williamson hybrid nanofluids on a stretching cylindrical surface. In this model we have taken Ethylene Glycol (EG 50%) and Water ( $H_{2}O$ 50%) as the base fluid and $Cu-A{l}_2{O}_3$ as the nanoparticles. There are various theoretical models available presently for illustrating the thermal transfer impact of non-Newtonian liquid flows over a cylinder. Additionally, External magnetic forces are ideal for addressing the fluid's physical properties and controlling the sort of heat and momentum transfer in the system. Taking this into perspective, we investigate the heat transport behaviour of two distinct non-Newtonian MHD fluids when a cylinder is stretched with heat generation, using a new heat flux theory developed by Christov–Cattaneo to explain the heat transport behaviour. The basic PDEs are turned into ODEs by using the correct similarity transformations. The 4^th order Runge–Kutta shooting system is used to solve these ODEs. Homotopy perturbation method (HPM) for the nonlinear system is developed for the comparison purpose and more accurate and reliable outcomes is illustrated through graphs and tables. It is observed that the fluid velocity reduces for the higher values of M. Higher values of the heat generation parameter improve the temperature profile. Nusselt number diminishes when developing Brinkman and Eckert number. Thermal relaxation effectively augments the Bejan factor in the flow of Williamson fluid more than it does in the flow of Casson fluid. This type of theoretical study may be used to improve the performance of solar collectors, solar water heating, solar energy, domestic baseboard heaters, industrial heat exchangers and so on.