Darcy flow of unsteady Casson fluid subject to thermal radiation and Lorentz force on wavy walls: Case of slip flow for small and large values of plastic dynamic viscosity

Abstract

This article describes the evolution of the velocity slip and heat transfer effects on the magnetohydrodynamic oscillatory flow of Casson fluid in a wavy channel immersed in a porous medium in the presence of thermal radiation. The Casson fluid model is used to describe non-Newtonian fluid behaviour. Analytical solutions to the dimensionless governing equations are compared to the numerical outcomes produced by MATLAB's built-in numerical solver, bvp4c. The effect of various physical parameters on momentum and energy profiles of the Casson fluid is analysed. This report also examines a parametric analysis illustrating the impact of the Nusselt number and Casson parameter. Increased velocity fields result from higher values of the thermal radiation and Casson-Viscous parameters. When thermal radiation increases, the impact of thermal diffusivity and temperature increases, and the Prandtl number suppresses the temperature distribution. Furthermore, one slip parameter decreases the velocity field while the other increases fluid velocity. For various values of viscous and radiation parameter, the variations for skin friction coefficient and Nusselt number occur periodically because of the asymmetric wavy motion. A comparative study is carried out to characterise Newtonian and non-Newtonian fluid behavior by analyzing the velocity for β – small (non-Newtonian fluid) and β – large (Newtonian fluid) values of plastic dynamic viscosity using linear slope regression analysis.