Entropy optimized assisting and opposing non-linear radiative flow of hybrid nanofluid
M.K. Nayak, Fazle Mabood, Abdul Sattar Dogonchi, K. Ramadan, Iskander Tlili, Wakar A. Khan
Abstract
A numerical treatment on flow and heat transfer of radiative hybrid nanofluid comprising of Al2O3 and Cu nanoparticles and water as base fluid past an isothermal stretched cylinder set in a porous medium is conducted. The Al2O3 - Cu/water hybrid nanofluid has higher thermal conductivity than single Al2O3 and Cu and better heat transfer efficiency with low concentration. Therefore, practical applications of hybrid nanofluids in heat transfer systems such as solar collectors, heat pipes, heat exchangers, mini channel heat sink, and others could have a significant impact for its better chemical stability, mechanical resistance, physical strength, and augmented thermal conductivity. Both assisting and opposing flows are taken into consideration. Entropy optimization analysis is explored elaborately. Having transformed into non dimensional form through use of similarity variables, governing equations are solved by bvp4c solver in Matlab software. The outcomes of the numerical solution are that inclusion of more and more porous matrix whittles down non-linear radiative flow of Al2O3 - Cu/water hybrid nanofluid, and growth of curvature parameter peters out drag coefficient and heat transfer rate under influence of assisting and opposing flows. Besides, entropy generation rate is significantly higher for Al2O3 - Cu/water hybrid nanofluid than individual Al2O3 - water nanofluid or Cu - water nanofluid in both assisting and opposing flows.