Numerical Investigation of Exergy and Entropy Analysis for W/EG-Based Non-newtonian Hybrid Nanofluid for Helically Corrugated Tube Heat Exchanger

In this study, the second law analysis of ethylene glycol-based TiO2-SiO2 non-Newtonian hybrid nanofluid under turbulent flow conditions has been investigated. A helically corrugated tube is used to examine the effect of corrugation-height ratio (e/dh) and volume fraction (φ) on entropy generation rate and the second law efficiency. These tubes are widely preferred in many engineering applications, such as pharmaceuticals, naval, paint production, food industry, heat exchangers, chemical process and gas industries. ANSYS FLUENT 19.0 is used to simulate the model with the corrugated wall maintained at a constant heat flux of 25 kW/m2 with a range of volume flow rate of hybrid nanofluid from 15 to 25 lpm. The use of corrugation with hybrid nanofluid shows a promising result from the point of view of the second law of thermodynamics. The entropy generation rate and the exergy destruction rate of the HCT decrease as the corrugation height and the particle volume fraction increase. Furthermore, second law efficiency increases with both e/dh and φ.