Table of Contents
ISRN Mechanical Engineering
Volume 2014 (2014), Article ID 274560, 5 pages
Research Article

The Effect of Nanoparticles on Thermal Efficiency of Double Tube Heat Exchangers in Turbulent Flow

1Department of Chemistry, Islamic Azad University, Arak Branch, Arak 38361-1-9131, Iran
2Department of Chemistry, Islamic Azad University, Saveh Branch, Saveh 39197-15179, Iran
3Department of Chemical Engineering, Faculty of Sciences, University of Arak, Arak 38156-8-8349, Iran

Received 7 February 2014; Accepted 11 March 2014; Published 27 March 2014

Academic Editors: M. Al-Nimr and M. Yürüsoy

Copyright © 2014 Reza Aghayari et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


This paper refers to the Overall Heat Transfer Coefficient of Nano Fluids (OHTCNF) in heat exchangers and the relevant effective parameters. An improvement in Heat Transfer (HT) and OHTCNF containing nanoaluminum oxide with ca. 20 nm particle size and particular volume fraction in the range of 0.001-0.002 has been reported. The effects of temperature and concentration of nanoparticles on HT variation as well as Overall Heat Transfer Coefficient (OHTC) in a countercurrent double tube heat exchanger with turbulent flow have been studied. The experimental results show a remarkable 8%–10% rise in the mean HT and the OHTC. Accordingly, with an increase in the processing temperature and/or particle concentration the OHTC was observed to increase.