Impact of Arrhenius Activation Energy on Cu/Ethylene Glycol Nanofluid Past a Rotating Disk with an Aligned Magnetic Field

Abstract

This investigation examines the momentum, thermal, and species transport characteristics of an ethylene glycol-based copper nanofluid over a rotating disk configuration, incorporating the combined influences of an aligned magnetic field and Arrhenius activation energy. The mathematical model, comprising nonlinear partial differential equations for momentum conservation, energy balance, and concentration distribution, is reduced to a system of ordinary differential equations through appropriate similarity transformations. Numerical solutions are obtained using the BVP5C algorithm, yielding detailed velocity, temperature, and concentration profiles across the boundary layer.

The principal novelty of this work lies in the simultaneous consideration of activation energy effects and aligned magnetic field orientation on nanofluid behavior in rotating disk geometry, a combination not previously addressed in the literature. A systematic parametric study examines how key physical quantities like magnetic field intensity, nanoparticle volumetric concentration, activation energy parameter, and Schmidt number—influence the heat and mass transfer characteristics of the system.

The results demonstrate that increasing magnetic field strength produces a retarding effect on fluid motion, with both radial and tangential velocity components diminishing as the Lorentz force intensifies. Furthermore, the activation energy parameter exhibits a pronounced influence on species transport, significantly modifying concentration distributions and mass transfer rates at the disk surface. These findings contribute to the fundamental understanding of nanofluid behavior under coupled magnetic and chemical reaction effects, with potential implications for thermal management systems and biomedical applications