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In various industrial applications, the main objective is to enhance thermal efficiency by minimizing the generation of entropy. Specifically, achieving optimal thermal efficiency in a tilted cylindrical chamber poses significant challenges due to the combined effects of tangential and normal gravity components. Our study focuses on the flow dynamics, thermal transport, and entropy generation of Fe3O4/H2O nanoliquid within a cylindrical annular enclosure by incorporating the synergistic effects of magnetic force, geometric inclination angle, and thickness of the porous region. The Brinkman–Forchheimer-extended Darcy model for ferrofluid motion and the one-equation model for heat transfer are applied in the porous region, while the conventional Navier–Stokes and energy equations are used in the fluid-only region. A series of computations is performed for various key parameters, such as Hartmann number (0 ≤ H a ≤ 60), Darcy number ( 10 − 5 ≤ D a ≤ 10 − 1 ), porous layer thickness (0.1 ≤ ε ≤ 0.9), and angle of inclination (− 60 ° ≤ γ ≤ 60 °). Our results reveal that the heat transport rate is enhanced by 48.6% with an increase in the Darcy number from 10 − 5 to 10 − 1 . Moreover, the flow circulation and heat transport can be optimized by tilting the enclosure anticlockwise. It has been found that 91.8% of flow strength can be enhanced by rotating the enclosure from −60° to 60°. Finally, this study suggests that the inclination angle of 30° and a porous layer thickness of 0.3 emerge as the ideal configuration to obtain optimal performance, particularly for lower Hartmann and higher Darcy numbers. Our findings will provide insight into optimizing thermal processes in nanoliquid-filled enclosures subjected to magnetic force. [ABSTRACT FROM AUTHOR]

The primary challenge in the majority of heat transfer applications, in view of design perspective, is to maximize the thermal transport with the minimum generation of entropy. This paper addresses the numerical investigation of buoyant convection and entropy generation processes of Al2O3–water nanofluid inside a vertical annular configuration having two coaxial cylinders. The vertical cylindrical surfaces are imposed with sinusoidal thermal distribution having different phase deviation and amplitude, while the horizontal surfaces are retained adiabatic. In this analysis, the numerical computations of conservation equations governing the physical process are performed using the time‐splitting technique and line overrelaxation methods. Detailed numerical simulations are performed for broad ranges of critical parameters, such as Rayleigh number, phase deviation, amplitude ratio, and nanoparticle volume fraction. From the vast numerical experiments, we systematically identified the suitable parameter regimes at which enhanced thermal transport has been produced with minimum entropy generation. Furthermore, the critical quantities, such as thermal dissipation and entropy generation, could be effectively monitored by a particular selection of phase deviation (γ) and amplitude ratio (ε). It has been identified that these parameters have more influence on thermal transport as well as entropy production as compared to other parameters of the analysis. [ABSTRACT FROM AUTHOR]