Influence of various shape factors on a hybrid nanofluid flow over a convectively heated exponential stretching sheet with exponential heat source and activation energy: An irreversibility analysis

Abstract

Understanding and controlling the shape factors of nanoparticles in fluid flow problems is crucial for optimizing heat transfer, fluid dynamics, and various applications such as nanofluids, drug delivery systems, catalysis, and nanocomposites. By tailoring the shape of nanoparticles, researchers can manipulate their behavior, dispersion, and interaction with the fluid, thereby optimizing the desired outcomes in various fluid flow problems. In this work, we investigated how thermal radiation, exponential heat source, and activation energy parameters affect the laminar flow properties of a hybrid nanofluid (Water + Graphene + Multi-Walled (MW) Carbon Nanotubes (CNTs)) over an exponentially expanding sheet. This article also includes an analysis of irreversibility. The equations required to represent the problem have been turned into a system of nonlinear ordinary differential equations, and this system has been unraveled by means of the bvp4c solver. Outcomes are presented for three instances, i.e. platelet, cylinder, and spherical shape factors. It is observed that there is an increase in the formation of entropy associated with the upsurge in the values of the Brinkman number, but there is an inverse proportional relation between activation energy () and entropy generation. It is clear from a closer inspection that as the friction factor declines with the escalation in the magnetic field parameter () and volume fraction of graphene (). At the skin friction coefficient is seen to drop at a rate of 0.69807 (in all cases). It is discovered that, when (Prandtl number), the Nusselt number declines by 0.009161 (platelet shape), 0.009397 (cylinder shape), and 0.009997 (spherical shape). It is remarked that the transmission rate of mass declines with the rise in At the Sherwood number is seen to drop at a rate of 0.30723 (platelet shape), 0.30718 (cylinder shape), and 0.30708 (spherical shape).