Influence of boundary condition variations on magnetohydrodynamics natural convection and entropy generation in a ternary nanofluid filled-square cavity with elliptic cylinder

The present study numerically investigates the effects of three distinct boundary condition configurations on inclined magnetohydrodynamics natural convection flow and entropy generation within a square cavity containing a trihybrid nanofluid. The flow is induced by an isothermally heated internal elliptic cylinder, while the cavity is filled with a trihybrid nanofluid composed of multiwall carbon nanotubes (MWCNT), titanium oxide (TiO2), and ferric oxide (Fe2O3) suspended in ethylene glycol. The enclosure is subjected to varying inclination angles and an externally applied magnetic field. The numerical simulations are performed using a custom-developed code implemented in the FORTRAN programing language. The computational methodology employed to solve the coupled governing equations of continuity, momentum, energy, and entropy generation along with the corresponding boundary conditions relies on the finite volume method (FVM) and Full Multigrid Acceleration. This study systematically examines various wake parameters, including the inclination angle of the cavity (γ), the orientation of the applied magnetic field (χ), the Hartmann number (Ha), the Rayleigh number (Ra), the volume fraction of the trihybrid nanofluid (ϕ), and three distinct thermal boundary condition configurations within the proposed model. The major findings issued from the impact of these parameters on the fluid flow and heat transfer characteristics reveal that the thermal boundary conditions of the configuration C3 exhibited the best trade-off between heat transfer enhancement and entropy minimization under specific conditions that will be mentioned in the paper. The insights gained from this study provide a deeper understanding of the interplay between thermal boundary conditions, magnetic field orientation, cavity inclination, and trihybrid nanofluid composition, offering valuable guidance for optimizing thermal management systems in engineering and industrial applications.