Numerical study of micro polar fluid flow over a stretching sheet with darcy–forchheimer drag, thermal radiation, dufour effect, and heat source

This study is significant for advancing the design of porous heat-transfer systems such as geothermal exchangers, catalytic reactors, and polymer processing units by analyzing how multiple physical mechanisms jointly influence micropolar fluid behavior. The work numerically investigates the combined effects of Darcy–Forchheimer drag, thermal radiation, Dufour diffusion, and internal heat generation on the flow, micro rotation, and heat-transfer characteristics of a micropolar fluid over a stretching sheet embedded in a porous medium.The governing nonlinear partial differential equations were transformed into coupled ordinary differential equations through similarity transformations and solved using the Runge–Kutta–Fehlberg (RKF45) method with a shooting technique to ensure convergence and precision. Results reveal that Darcy and Forchheimer parameters substantially reduce fluid velocity due to enhanced porous resistance, whereas radiation and heat-generation parameters elevate the temperature profile within the boundary layer. An increase in the micropolar coupling parameter intensifies micro rotation and modifies near-wall shear stress behavior, while the Darcy number exhibits the strongest influence by markedly decreasing the heat-transfer rate as porosity resistance rises. Despite extensive research on micropolar and nanofluid flows through porous media, few studies have addressed the combined nonlinear influence of Darcy–Forchheimer drag, radiative heat transfer, Dufour diffusion, and internal heat generation. The present unified model incorporates these mechanisms to capture their interactive effects on momentum and energy transport, offering new physical insights for optimizing thermal management in porous and radiative fluid systems.