ENERGY, ENTROPY AND EXERGY ANALYSES OF HYBRID NANOFLUID FLOW IN A TRAPEZOIDAL CHANNEL

Abstract

This study presents energy, entropy, and exergy analyses of Al2O3-Cu/water hybrid nanofluid flow in a trapezoidal cross-sectioned channel under a turbulent regime (10⁴<Re<10⁵) for the first time. Understanding the main source of the entropy generation along the channel, also obtaining the total entropy variation of hybrid nanofluid comparing to single nanofluids (Al2O3/water and Cu/water) and base fluid is pursued objective. In other to perform these aforementioned analyses, a realistic model, in which all formulas are derived, is developed and thermodynamic concepts such as exergy efficiency and exergy destruction for hybrid nanofluid flow in a non-circular cross-sectioned channel are discussed for the first time. Results obtaining from the analyses of both hybrid and single nanofluids have been compared and discussed for volumetric concentrations of 1.0% and 2.0%. As a result, it is obtained that 2.0% volume concentration hybrid nanofluid offers the best convective heat transfer performance with 34% enhancement and best exergetic performance. Furthermore, hybrid nanofluid has the lowest entropy generation value.

Keywords

• Hybrid Nanofluid
• CFD
• Turbulent Flow
• Convective Heat Transfer
• Energy
• Entropy
• Exergy Analyses

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