Second law analysis of MHD convection of a radiating nanofluid within the gap between two inclined concentric pipes

Abstract

This paper theoretically examined the inherent irreversibility in hydromagnetic mixed convection of a radiating adjustable viscosity nanofluid between two concentric inclined cylindrical pipes. Thermodynamics’ first and second laws are incorporated into the two-phase nanofluid flow model problem to explore the repercussions of thermophoresis, Brownian motion, inclination angle, Joule heating, buoyancy forces, viscous dissipation, thermal radiation and entropy generation rate on the overall flow structure with temperature and nanoparticles concentration distribution. The nonlinear model equations of differential types are obtained and numerically addressed through shooting quadrature in conjunction with the Runge–Kutta–Fehlberg integration scheme. Relevant outcomes are graphically represented and discussed. The findings indicate that a rise in the inclination angle lessens the buoyancy effects and diminishes the entropy generation rate in the annular region of the concentric pipes. Within the annulus, the irreversibility due to heat and mass transfer dominates the entropy generation rate. In contrast, an upsurge in magnetic field intensity decreases the entropy generation rate and the Bejan number.