A review of the effect of nanofluids to reduce water loss and improve thermal properties in cooling towers

Document Type : Review Article

Authors

Department of Renewable Energies and Environment, Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

Abstract

In most of the factories, one of the most important and practical devices is the type of cooling towers which are used to release extra heat from processes in various industries to the environment. This study is an overview of novel ways on the effect of different type’s nanofluids on the thermal performance and reduce the amount of flowing water down the cooling tower. Nanofluids can improve thermo physical properties such as heat capacity& thermal conductivity coefficient and increase density & viscosity in comparison to base fluid. The dispersion of the nanoparticle increases the surface tension of the nanofluid and increases the resistance to water evaporation.So in this paper study influence of ZnO/water, nonporous graphene, AL2O3/ water, TiO2/water, CuO/water with the different concentration in order to improve cooling tower performance.
It was found that by using nanofluids, cooling range, cooling tower characteristic (TC), volumetric heat transfer coefficient and efficiency are enhanced in comparison to water. For example, TC enhanced by 21.5% and 22.5% for ZnO/water nanofluid with concentration of 0.02 wt% and 0.05 wt%, respectively. In continue, results of sensitivity analyses that has been carried out in investigations, are discussed.

Keywords


[1]. Askari S, Lotfi R, Seifkordi A, Rashidi AM, Koolivand H. A novel approach for energy and water conservation in wet cooling towers by using MWNTs and nanoporous graphene nanofluids. Energy conversion and management. 2016 Feb 1;109:10-8.
[2]. Zhai Z, Fu S. Improving cooling efficiency of dry-cooling towers under cross-wind conditions by using wind-break methods. Applied Thermal Engineering. 2006 Jul 1;26(10):1008-17.
[3]. Imani-Mofrad P, Saeed ZH, Shanbedi M. Experimental investigation of filled bed effect on the thermal performance of a wet cooling tower by using ZnO/water nanofluid. Energy Conversion and Management. 2016 Nov 1;127:199-207.
[4]. Xie X, Zhang Y, He C, Xu T, Zhang B, Chen Q. Bench-Scale Experimental Study on the Heat Transfer Intensification of a Closed Wet Cooling Tower Using Aluminum Oxide Nanofluids. Industrial & Engineering Chemistry Research. 2017 May 12;56(20):6022-34.
[5]. Goodarzi, M., Kiasat, M., Influence of nanoparticle immersed in water on Thermal performance of wet cooling tower. 1th tajhizatconf., Dec. 2013. Tehran, Iran. [Persian].
[6]. Babu JR, Kumar KK, Rao SS. State-of-art review on hybrid nanofluids. Renewable and Sustainable Energy Reviews. 2017 Sep 1;77:551-65.
[7]. Esfe MH, Alirezaie A, Rejvani M. An applicable study on the thermal conductivity of SWCNT-MgO hybrid nanofluid and price-performance analysis for energy management. Applied Thermal Engineering. 2017 Jan 25;111:1202-10.
[8]. Yarmand H, Gharehkhani S, Ahmadi G, Shirazi SF, Baradaran S, Montazer E, Zubir MN,
Alehashem MS, Kazi SN, Dahari M. Graphene nanoplatelets–silver hybrid nanofluids for enhanced heat transfer. Energy conversion and management. 2015 Aug 1;100:419-28.
[9]. Rao RV, Patel VK. Optimization of mechanical draft counter flow wet-cooling tower using artificial bee colony algorithm. Energy Conversion and Management. 2011 Jul 1;52(7):2611-22.
[10]. Atarzadeh MA, Rasouli S, Mehmandoust B. Numerical Analysis the Equations of Heat and Mass Transfer in Cooling Towers. Department of Mechanical Engineering, Islamic Azad University, Khomeini Shahr Branch, Khomeini Shahr, Iran. 2015.
[11]. Alavi SR, Rahmati M. Experimental investigation on thermal performance of natural draft wet cooling towers employing an innovative wind-creator setup. Energy conversion and management. 2016 Aug 15;122:504-14.
[12]. Azad AV, Azad NV. Application of nanofluids for the optimal design of shell and tube heat exchangers using genetic algorithm. Case Studies in Thermal Engineering. 2016 Sep 1;8:198-206.
[13]. Pak BC, Cho YI. Hydrodynamic and heat transfer study of dispersed fluids with submicron metallic oxide particles. Experimental Heat Transfer an International Journal. 1998 Apr 1;11(2):151-70.
[14]. Lim S, Horiuchi H, Nikolov AD, Wasan D. Nanofluids alter the surface wettability of solids. Langmuir. 2015 May 21;31(21):5827-35.
[15]. Bhuiyan MH, Saidur R, Amalina MA, Mostafizur RM, Islam AK. Effect of nanoparticles concentration and their sizes on surface tension of nanofluids. Procedia Engineering. 2015 Jan 1;105:431-7.