Fluid flow and heat transfer analysis of a ternary aqueous Fe3O4 + MWCNT + Cu/H2O magnetic nanofluid in an inclined rectangular porous cavity

The natural convective flow and heat transfer efficiency within a cavity have been utilized in various applications, such as solar collectors, heat exchangers, and cooling electronic devices. Ternary nanofluids have higher heat transfer features than nanofluids. Motivated by the aforementioned applications, the current study investigates the natural convective flow and thermal efficiency features of Fe3O4 + MWCNT + Cu/H2O electroconductive ternary nanofluid-filled inclined, partially heated rectangular porous cavity under the impacts of an inclined magnetic field, heat source/sink, Joule heating, a resistance porous medium, and viscous dissipation. Additionally, to examine the best heat transfer rate performance of ternary nanofluids, different combinations of aqueous-based ferromagnetic, metallic, and carbon-based nanoparticles' are also scrutinized. The considered system of equations with suitable initial-boundary conditions is solved by the Marker and Cell method. The results reveal that pertinent parameters such as Darcy number, Rayleigh number, cavity inclination angle, nanoparticle volume fraction, and heat source/sink have significant impacts on the convective flow regime. The investigation reflects that in the presence of a heat source, by augmenting the Fe3O4(33.3%), MWCNT(33.3%), and Cu(33.3%) nanoparticles' volume fractions from 1% to 5%, the average heat transfer rate is increased by 7.49%. By considering Fe3O4(10%),MWCNT(45%), and Cu(45%) nanoparticles, the average heat transfer rate can be increased up to 8.95%. Fe3O4(10%) + MWCNT(45%) + Cu(45%)/H2O ternary nanofluids deliver the highest, and Fe3O4(45%) + MWCNT(45%) + Cu(10%)/H2O ternary nanofluids produce the lowest rate of heat transfer among the other combinations of ternary nanofluids. This outcome ensures that a suitable combination of nanoparticles extensively improves the heat transfer characteristics of the base fluids.