TIME-DEPENDENT ENTROPY ANALYSIS IN MAGNETIZED CU-AL2O3/ETHYLENE GLYCOL HYBRID NANOFLUID FLOW DUE TO A VIBRATING VERTICAL PLATE

Experimental and theoretical studies performed over the past few years demonstrate that nanofluids are among the best tools for the enhancement of heat transfer characteristics. Very recently, it has been reported that a hybrid nanofluid is a new generation of working fluids. Therefore, we present a novel study to develop and understand a mathematical model for a non-Newtonian hybrid nanofluid flow under a magnetic environment. Focusing on this agenda, the main concern of the present article is to elaborate on the features of energy transportation and entropy generation attributable to time-dependent magnetohydrodynamic boundary layer flow of a non-Newtonian Casson hybrid nanofluid past a vibrating vertical plate with slip condition and Newtonian heat flux inspired by the thermal radiation phenomenon. The Casson fluid model is considered here to describe the rheological behavior of the non-Newtonian fluid. Ethylene glycol (EG) is used as a common Casson fluid. Cu and Al2O3 nanoparticles are dispersed in EG for constructing the hybrid nanofluid. The Cogley-Vincenti-Giles non-gray flux model is adopted to simulate the radiative heat flux in the energy equation. The exact analytical solution of the governing equations is provided by applying the Laplace transform method. The expressions for the entropy generation rate and the Bejan number are also derived. Impacts of emerging flow parameters on the pertinent flow characteristics are elaborated through graphs and tables. Computational analysis reveals that the entropy generation rate and Bejan number highly fluctuate with the frequency of oscillations of the plate. A comparison of flow dynamics due to Casson nanofluid (Cu-EG) and Casson hybrid nanofluid (Cu-Al2O3/EG) flows is recorded. The entropy generation is minimum in copper-alumina-ethylene glycol in comparison to copper-ethylene glycol. The proposed model finds valuable applications in power transmission systems, design of nuclear reactors where the moving plate is used as a control rod, and design of the compression molding process in nanoscale partnering.