Magneto-double-diffusive natural convection and irreversibility analysis of a nanofluid flowing in an annular concentric space

Abstract

In the present article, magneto-double-diffusive density driven convection accompanied by an entropy optimization analysis of Al2O3-water nanofluid filled in a horizontal coaxial annular space is numerically addressed. The double-diffusive natural nanofluid flow which is produced due to the maintaining of constant and different temperature and solute on the inner and outer cylinders is affected by a uniform vertical magnetic field. Dimensionless governed equations which are developed through law of conservation of mass, momentum, and energy are numerically solved via finite volume approach, and parametric control analysis is developed. By using Corcione empirical correlations considering the Brownian diffusion of 4% of Al2O3 nanoparticles in water, the thermal conductivity and viscosity of the mixture nanofluid are determined. Results are performed and interpreted in detail for wide range of relevant variables: Rayleigh (102 ≤ Ra ≤ 105), Hartmann (0 ≤ Ha ≤ 30), Lewis numbers (0 ≤ Le ≤ 10), and Buoyancy ratio (−4 ≤ N ≤ 4) to evaluate the double-diffusive convective nanofluid flow, heat and solute transfer rates as well as entropies produced in the system.