Second law analysis of nanofuid laminar flow in a counter-flow heat exchanger

Authors

Abstract

In this paper the results of numerical simulations for heat transfer of a nanofluid flow inside a counter flow heat exchanger is presented. Effects of addition oftheAl2O3 nanoparticles on the entropy generation ofthesystem are investigated. Single fluid model is used for simulation of the nanofluid flow. Analytical and experimental formulations are used for density, specific heat, viscosity and conductivity of nanofluid. Finite volume method (FVM) has been used for numrerical simulation and SIMPLE algorithm is applied for pressure velocity coupling. It is found that adding nano particles in annulus, causes a little incerement in entropy generation which can be overlooked. On the other hand, the increasing of volume fraction of nanoparticles leads to ascend heat transfer coefficient (U ) and total heat transfer (Q) significantly, and it results in decreased entropy number (Ns).

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