Thermal conductivity and viscosity measurements of water-based TiO 2 nanofluids
Küçük Resim Yok
Tarih
2009
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
In this study, the thermal conductivity and viscosity of TiO 2 nanoparticles in deionized water were investigated up to a volume fraction of 3% of particles. The nanofluid was prepared by dispersing TiO 2 nanoparticles in deionized water by using ultrasonic equipment. The mean diameter of TiO 2 nanoparticles was 21 nm. While the thermal conductivity of nanofluids has been measured in general using conventional techniques such as the transient hot-wire method, this work presents the application of the 3? method for measuring the thermal conductivity. The 3? method was validated by measuring the thermal conductivity of pure fluids (water, methanol, ethanol, and ethylene glycol), yielding accurate values within 2%. Following this validation, the effective thermal conductivity of TiO 2 nanoparticles in deionized water was measured at temperatures of 13 °C, 23 °C, 40 °C, and 55 °C. The experimental results showed that the thermal conductivity increases with an increase of particle volume fraction, and the enhancement was observed to be 7.4% over the base fluid for a nanofluid with 3% volume fraction of TiO 2 nanoparticles at 13 °C. The increase in viscosity with the increase of particle volume fraction was much more than predicted by the Einstein model. From this research, it seems that the increase in the nanofluid viscosity is larger than the enhancement in the thermal conductivity. © 2009 Springer Science+Business Media, LLC.
Açıklama
Anahtar Kelimeler
3? method, Nanofluid, Nanoparticle, Thermal conductivity, Titanium dioxide, Viscosity
Kaynak
International Journal of Thermophysics
WoS Q Değeri
Scopus Q Değeri
Q3
Cilt
30
Sayı
4
