Effects of hall current and thermal radiation on entropy generation in MHD tangent hyperbolic nanofluid flow

Abstract

This study investigates the effects of Hall current, thermal radiation, and entropy generation on the magnetohydrodynamic flow of a tangent hyperbolic Al₂\(\text{O}\)₃ nanofluid with a 50% ethylene glycol-50% water (\(EG\)-H₂\(\text{O}\)) base fluid over a linearly stretching surface. The novelty of the present work lies in analysing the combined influence of Hall current and entropy generation on a non-Newtonian tangent hyperbolic nanofluid under magnetic field effects. The governing nonlinear partial differential equations are transformed into coupled ordinary differential equations using suitable similarity transformations and solved numerically through the Runge–Kutta–Fehlberg method. The results indicate that increasing the Hartmann number significantly suppresses both primary and secondary velocity profiles due to enhanced Lorentz force resistance, whereas the Hall parameter weakens the magnetic damping effect and enhances the secondary flow. Entropy generation decreases with increasing Hartmann number, nanoparticle volume fraction, and Weissenberg number owing to the reduction in viscous and thermal irreversibility. In addition, the local Nusselt number decreases with increasing magnetic field strength, radiation parameter, and heat source parameter. The present numerical results exhibit excellent agreement with previously published studies, with a maximum error below 0.1%, confirming the accuracy of the computational method. These findings are useful in the design of MHD pumps, cooling technologies, polymer processing, and thermal energy transport systems involving electrically conducting non-Newtonian nanofluids.