Generalized thermal investigation of unsteady MHD flow of Oldroyd-B fluid with slip effects and Newtonian heating; a Caputo-Fabrizio fractional model

Abstract

This article critically examines the influences of Newtonian heating and slip effects on unsteady magnetohydrodynamic (MHD) flow of an Oldroyd-B fluid near an infinitely long plate. The nonlinear thermal radiation influence is considered in normal direction to the vertical plate. A modern definition of Caputo-Fabrizio fractional derivative is applied to generalize the constitutive mass and energy equations. The Laplace transformation technique and Durbin’s numerical algorithm are served to develop the solutions of proposed problem. The solutions are determined for both fractional and ordinary cases and Stehfest’s and Zakian’s numerical algorithms are employed to secure the authenticity of these solutions. The relations for Nusselt number and skin friction coefficient are efficiently computed to precisely estimate the shear stress and rate of heat transfer at boundary. The respective numerical computations are accessible through tables. To comprehensively analyze the dynamics of the proposed problem, physical influence of various parameters is studied and repercussions are graphically highlighted and discussed. Furthermore, two limiting models named as second grade model and Maxwell model are deduced to compare the pertinent flow characteristics. A comparative analysis between fractional and classical models depicts that the Caputo-Fabrizio fractional model explains the memory effects more adequately.

Keywords

• Newtonian heating
• Caputo-Fabrizio fractional derivative
• Laplace transform
• Oldroyd-B fluid
• Slip effect
• MHD