RESUMO
This study aimed at studying the variational effect of nonlinear thermal radiation on the flow of Casson nanofluid ( Al 2 O 3 - Blood ${\rm Al}_2 {\rm O}_3\text{-}{\rm Blood}$ ) through a porous microchannel with entropy generation. The novelty of this investigation includes the incorporation of porous media, nonlinear radiative heat flux, and convective heat transfer at the channel interface into the energy equation, which results in an enhanced analysis for the cooling design and heat transfer of microdevices that utilize Al 2 O 3 - Blood ${\rm Al}_2 {\rm O}_3\text{-}{\rm Blood}$ nanofluid flow. Particularly, alumina (Al2 O3 ) is considered as the nanoparticles in this blood base fluid due to associated advanced pharmaceutical applications. With dimensionless variables being utilized, the governing equations are minimized to their simplest form. The Chebysev-based collocation technique was employed to numerically solve the resultant ordinary differential equations with the associated boundary conditions and the impact of flow, thermal, and irreversibility distribution fields are determined through graphs. The findings identified that higher levels of Hartmann number produce the Lorentz force, which limits fluid flow and lowers velocity, the response of nonlinear thermal radiation diminishes the heat transfer rate, and a rise in the Casson parameter also reduces the Bejan number. The results of this research can be used to improve heat transfer performance in biomedical devices, design-efficient energy conversion cycles, optimize cooling systems, and cover a wide range of energy technologies from renewable energy to aerospace propulsion.