Entropy generation optimisation in the Maxwell hybrid nanofluid flow through an inclined shrinking sheet when Soret, Dufour and couple stress are significant

Abstract

The study of fluid flow over a shrinking sheet is a fundamental problem in fluid mechanics with applications in diverse fields. The concept emerged from the need to understand the behaviour of fluids in contact with moving surfaces that undergo deformation. Understanding the fluid dynamics and heat transfer characteristics of flow over a shrinking sheet is crucial for optimising industrial processes such as polymer processing, metallurgy and paper production. The present work investigates the flow and heat transmission properties of a Maxwell hybrid nanofluid over a shrinking sheet while subjected to various parameters including thermal radiation. The influence of magnetic field, couple stress, Weissenberg number, nanoparticle concentration, Eckert number, thermal radiation, Dufour number, Soret number and chemical reaction on fluid flow, Nusselt number, mass transmission, entropy generation and Bejan number are investigated. The governing equations are transformed and solved numerically using the bvp4c solver. The key findings reveal that a stronger magnetic field and higher nanoparticle concentration impede fluid flow, while higher couple stress parameter ([Formula: see text]) and lower Weissenberg number enhance it. Dufour parameter ([Formula: see text]) and Eckert number elevate the temperature, whereas a stronger chemical reaction depletes the solute concentration. The study also explores the interplay between viscous dissipation and thermal diffusion on entropy generation and Bejan number. Finally, the influence of various parameters on the skin friction coefficient, Nusselt number and Sherwood number is presented. At [Formula: see text] there is a noticeable decrease in the friction coefficient, with a rate of 0.08906. It has been revealed that for values of Dufour number within the range of 0.1 to 1.3, there is a notable decrease of 0.05776 in the Nusselt number. For values of Soret number within the range of 0 to 3, it becomes apparent that the Sherwood number demonstrates a consistent downward trend, characterised by a rate of 0.02235.