Second law analysis of A L 2 O 3 -water nanofluid turbulent forced convection in a circular cross section tube with constant wall Temperature

Abstract

The present paper proposes an analysis based on the second principle of thermodynamics applied to a water-Alnanofluid. The nanofluid flows inside a circular section tube subjected to constant wall temperature. The aim of the investigation is to understand, by means of an analytical model, how entropy generation within the tube varies if inlet conditions, particles concentration, and dimensions are changed. To gather these information is of fundamental importance, in order to optimize the nanofluid flow. The results show that according to the inlet condition, there is a substantial variation of the entropy generation, particularly when Reynolds number is kept constant there is an increase of entropy generation, whereas when mass flow rate or velocity are taken constant, entropy generation decreases. © 2013 Vincenzo Bianco et al.