Asian Research Journal of Mathematics

Non-Newtonian nanofluid flow over stretching surfaces is crucial in many industrial applications, where nanoparticles, magnetic fields, and thermal effects significantly enhance heat transfer and fluid behavior. Advanced models, particularly the Powell–Eyring fluid framework, effectively capture complex rheological behavior, making them essential for accurately analyzing flow and heat transfer over radially stretching surfaces in realistic engineering processes. This study investigates the unsteady magnetohydrodynamic (MHD) radiative flow of a Powell–Eyring nanofluid over a radially stretching surface, incorporating viscous dissipation, Newtonian heating, and chemical reactions with activation energy. Using similarity transformations, the boundary-layer equations for momentum, energy, and concentration are reduced to a nonlinear system and solved numerically via MATLAB’s bvp4c. Thermal radiation is modeled using the Rosseland approximation, and reaction kinetics follow a temperature-dependent Arrhenius expression. Parametric analysis shows that the magnetic field and Eckert number suppress velocity while enhancing temperature. Velocity decreases with higher Darcy number and material parameter, but rises with the Powell–Eyring parameter. Temperature increases with Brownian motion, temperature difference, radiation, and Biot number, but decreases with Prandtl number. Concentration decreases with temperature difference, chemical reaction, Brownian motion, and Schmidt number, while it increases with concentration slip, activation energy, and thermophoresis. Effects on skin friction, Nusselt, and Sherwood numbers are quantified, highlighting the influence of key dimensionless parameters on momentum, heat, and mass transfer. These results guide the optimization of reactive nanofluid systems in energy-intensive and chemical processes.