IRREVERSIBILITY ANALYSIS IN Al2O3-WATER NANOFLUID FLOW WITH VARIABLE PROPERTY

Abstract

The present numerical work deals with the optimization of the micro-channel heat sink using irreversibility analysis. The nanofluid of Al2O3-water with the different nanoparticles concentration and the temperature-dependent property is chosen as a coolant. The flow is considered as fully developed, steady, and laminar in the constant cross-section of circular channels. Navier-Stokes and energy equations are solved for a single-phase flow with total mass flow rate and heat flow rate as constant. The objective functions related to the frictional and heat transfer irreversibilities are framed to assess the performance of the micro-channel heat sink. The optimum channel diameter corresponding to the optimum number of channels is determined at the lowest total irreversibility for both constant property solution and variable property solution. Designed optimum diameter is observed maximum for 2.5% Al2O3-water nanofluid with μ(T) variation followed by 1% Al2O3-water nanofluid with μ(T) variation, 2.5% Al2O3-water nanofluid with constant property solution, and 1% Al2O3-water nanofluid with constant property solution.