Exploration of entropy analysis and viscous dissipation on radially convective flow of (Cu-Al2O3:H2O) hybrid nanofluid over a stretching disk

Abstract

The current research work deals with the impact of suction/injection on the thermally radiating convective flow generated by a nonlinear stretched disk. The energy equation is addressed by the presence of thermal radiation and the energy dissipative function. This work was carried out with the help of the Das and Tiwari (single-phase nanofluid) models and the Maxwell Garnett and Brinkman nanofluid models for the analysis of entropy generation. In the present model, nanoparticles of copper (Cu) and alumina (Al₂O₃) are being used with water (H₂O) as the base fluid. The governing nonlinear partial differential equations are transformed into ordinary differential equations with the assistance of appropriate similarity variables. These transformed equations are then solved using the bvp4c function, a built-in function in MATLAB software. The investigation examines the influence of various factors on the velocity and temperature fields, entropy generation, skin friction, and heat transfer rate. The findings show that suction decreases velocity and temperature by 6.59%, while injection has the opposite effect. Viscous dissipation increases velocity by 5.13% and temperature by 17.94% in hybrid nanofluids. Higher Prandtl numbers reduce velocity and temperature by 6% in nanofluids but boost them by 5.45% and 18.81% in hybrid nanofluids with radiation growth. As volume fraction rises, Al₂O₃/H₂O nanofluid speed falls by 5.37%, but Cu-Al₂O₃/H₂O hybrid nanofluid temperature increases by 13.09% and surface drag force increases by 12%. The entropy of the hybrid nanofluid increases by 5.84%, 8.19%, and 14.04% with Eckert number, suction, and Prandtl number but decreases by 10.08% with temperature difference. The Nusselt number of nanofluid decreases by 10.58% and 12.40% with Eckert number and radiation, but hybrid particles increase it by 10.31% with intensified Prandtl number. These findings offer valuable insights for potential applications of hybrid nanofluids in heat transfer and cooling systems.