Skip to main content
Log in

The effect of particle size on the thermal conductivity of alumina nanofluids

  • Research Paper
  • Published:
Journal of Nanoparticle Research Aims and scope Submit manuscript


We present new data for the thermal conductivity enhancement in seven nanofluids containing 8–282 nm diameter alumina nanoparticles in water or ethylene glycol. Our results show that the thermal conductivity enhancement in these nanofluids decreases as the particle size decreases below about 50 nm. This finding is consistent with a decrease in the thermal conductivity of alumina nanoparticles with decreasing particle size, which can be attributed to phonon scattering at the solid–liquid interface. The limiting value of the enhancement for nanofluids containing large particles is greater than that predicted by the Maxwell equation, but is predicted well by the volume fraction weighted geometric mean of the bulk thermal conductivities of the solid and liquid. This observation was used to develop a simple relationship for the thermal conductivity of alumina nanofluids in both water and ethylene glycol.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others


C :

Exponent of Euler’s constant

k :

Thermal conductivity (W m−1 K−1)

q :

Heat dissipated per length of wire (W m−1)

r w :

Radius of wire (m)

T :

Temperature of wire (K)

t :

Time (s)


Thermal diffusivity of liquid (m2 s−1)


Volume fraction


Thermal conductivity enhancement

P :


l :



Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Amyn S. Teja.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Beck, M.P., Yuan, Y., Warrier, P. et al. The effect of particle size on the thermal conductivity of alumina nanofluids. J Nanopart Res 11, 1129–1136 (2009).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: