Analytical Investigation of Energy and Mass Transport in Magnetohydrodynamic Fe₃O₄–Water Nanofluid Flow through a Chemically Reacting Porous Channel with Thermal Radiation

Abstract

Magnetohydrodynamic (MHD) nanofluids have emerged as promising working fluids for advanced thermal management systems owing to their enhanced heat transfer capability and controllable transport characteristics under external magnetic fields. This study presents an analytical investigation of coupled energy and mass transport in Fe₃O₄–water nanofluid flow through a chemically reacting porous rectangular channel under the influence of thermal radiation. The novelty of the present work lies in the integration of established thermophysical property correlations for effective viscosity, thermal conductivity, and electrical conductivity with an analytical Laplace transform framework to investigate the combined effects of magnetic field, buoyancy, thermal radiation, nanoparticle volume fraction, and chemical reaction on transport phenomena in porous media. The governing momentum, energy, and concentration equations are formulated using the Buckingham π theorem to obtain the corresponding dimensionless model and are solved analytically using the Laplace transform technique, subject to the prescribed boundary conditions. The developed analytical solutions are employed to examine the influence of the governing dimensionless parameters on the velocity, temperature, and concentration distributions. The analytical results demonstrate that variations in nanoparticle volume fraction significantly modify the thermal and concentration fields through changes in the effective thermophysical properties of the Fe₃O₄–water nanofluid, while an increase in effective viscosity alters fluid momentum transport. The Hartmann number acts as a resistive parameter that suppresses the velocity profile through the Lorentz force, whereas the effects of thermal radiation and chemical reaction on the transport fields are shown to be consistent with the governing equations and the validated analytical solutions. Representative analytical results indicate that changes in the governing parameters produce measurable variations in the velocity, temperature, and concentration distributions under the investigated operating conditions. The proposed analytical model provides improved physical insight into coupled magnetohydrodynamic heat and mass transfer in chemically reacting porous media and offers a reliable theoretical framework for validating numerical models and supporting the design and optimisation of electronic cooling systems, porous thermal devices, energy conversion systems, and other engineering applications employing Fe₃O₄–water nanofluids.