EXPERIMENTAL INVESTIGATION ON THERMAL CONDUCTIVITY AND VISCOSITY OF NANOFLUIDS: PARTICLE SIZE EFFECT

TURGUT A., Saglanmak S., Doganay S.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, cilt.31, sa.1, ss.95-103, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 31 Sayı: 1
  • Basım Tarihi: 2016
  • Dergi Adı: JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Sayfa Sayıları: ss.95-103
  • Anahtar Kelimeler: Nanofluid, thermal conductivity, viscosity, particle size effect, CONVECTIVE HEAT-TRANSFER, THERMOPHYSICAL PROPERTIES, TRANSFER ENHANCEMENT, SUSPENSIONS, FLOW
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

Although, it has been more than a decade since research started on nanofluids, potential heat transfer fluids of next generation, there are still inconsistent and contradictory results between studies. Among these results, one is the effect of particle size on thermal performance of a nanofluid. In this study, thermal conductivity and viscosity of Al2O3 - deionized water nanofluids with different particle size (10 and 30 nm) and concentration (1 to 6.33 % vol.) were studied experimentally, and the results were compared with the effective thermal conductivity and effective viscosity models from the literature. It is observed that, particle size has no effect on the thermal conductivity of nanofluid and our experimental results are in a good agreement with Maxwell model, one of the classical effective thermal conductivity models. The results of the rheological measurements indicate that, nanofluid samples show a Newtonian fluid behavior and for the given particle volume concentration, bigger particle size gives a higher increase on the viscosity of the sample. Einstein model, one of the classical effective viscosity model, fails to predict the viscosity of nanofluid samples.