Nanofluids, that is liquids containing nanometer sized metallic or non-metallic solid nanoparticles, show an increase in thermal conductivity compared to that of the base liquid. In this paper a model for thermal conductivity of nanofluids based on the theory of Brownian motion of particles in a homogeneous liquid combined with the macroscopic Hamilton-Crosser model is presented. The model is shown to predict a temperature and particle size dependent thermal conductivity. Comparison between the predicted and experimental results show that the model is able to accurately predict the temperature and volume fraction dependence of the thermal conductivity of water based alumina and gold nanofluids.

1.
J. A. Eastman, S. U. S. Choi, S. Li, L. J. Thompson and S. Lee. Enhanced thermal conductivity through the development of nanofluids. Proceedings of the Symposium on Nanophase and Nanocomposite Materials II, 457: 3–11, 1997.
2.
Lee
S.
,
Choi
S. U. S.
,
Lu
S.
, and
Eastman
J. A.
.
Measuring thermal conductivity of fluids containing oxide nanoparticles
.
Journal of Heat Transfer
,
121
:
280
289
,
1999
.
3.
Eastman
J. A.
,
Choi
S. U. S.
,
Yu
W.
, and
Thompson
L. J.
.
Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles
.
Applied Physics Letters
,
78
(
6
):
718
720
,
2001
.
4.
Choi
S. U. S.
,
Zhang
Z. G.
,
Yu
W.
,
Lockwood
F. E.
, and
Grulke
E. A.
.
Anomalously thermal conductivity enhancement in nanotube suspensions
.
Applied Physics Letters
,
79
(
14
):
2252
2254
,
2001
.
5.
Xie
H.
,
Wang
J.
,
Xi
T.
,
Liu
Y.
,
Ai
F.
, and
Wu
Q.
.
Thermal conductivity enhancement of suspensions containing nanosized alumina particles
.
Journal of Applied Physics
,
91
(
7
):
4568
4572
,
2002
.
6.
Das
S. K.
,
Putra
N.
,
Thiesen
P.
, and
Roetzel
W.
.
Temperature dependence of thermal conductivity enhancement for nanofluids
.
Journal of Heat Transfer
,
125
:
567
574
,
2003
.
7.
Patel
H. E.
,
Das
S. K.
,
Sundararajan
T.
,
Nair
A. S.
,
George
B.
, and
Pradeep
T.
.
Thermal conductivities of naked and monolayer protected metal nanoparticle based nanofluids: manifestation of anomalous enhancement and chemical effects
.
Applied Physics Letters
,
83
(
14
):
2931
2933
,
2003
.
8.
Xie
H.
,
Lee
H.
,
Youn
W.
, and
Choi
M.
.
Nanofluids containing multiwalled carbon nanotubes and their enhanced thermal conductivities
.
Journal of Applied Physics
,
94
(
8
):
4967
4971
,
2003
.
9.
Keblinski
P.
,
Phillpot
S. R.
,
Choi
S. U. S.
, and
Eastman
J. A.
.
Mechanisms of heat flow in suspensions of nano-sized particles (nanofluids)
.
International Journal of Heat and Mass Transfer
,
45
:
855
863
,
2002
.
10.
Xue
L.
,
Keblinski
P.
,
Phillpot
S. R.
,
Choi
S. U. S.
and
Eastman
J. A.
.
Effect of liquid layering at the liquid-solid interface on thermal transport
.
International Journal of Heat and Mass Transfer
,
47
:
4277
4284
,
2004
.
11.
Jang
S. P.
, and
Choi
S. U. S.
.
Role of Brownian motion in the enhanced thermal conductivity of nanofluids
.
Applied Physics Letters
,
84
(
21
):
4316
4318
,
2004
.
12.
Bhattacharya
P.
,
Saha
S. K.
,
Yadav
A.
, and
Phelan
P. E.
.
Brownian Dynamics simulation to determine the effective thermal conductivity of nanofluids
.
Journal of Applied Physics
,
95
(
11
):
6492
6494
,
2004
.
13.
Xuan
Y.
,
Li
Q.
, and
Hu
W.
.
Aggregation structure and thermal conductivity of nanofluids
.
AIChE Journal
,
49
(
4
):
1038
1043
,
2003
.
14.
Xue
Q.
.
Model for effective thermal conductivity of nanofluids
.
Physics Letters A
,
307
:
313
317
,
2003
.
15.
Wang
B. X.
,
Zhou
L. P.
, and
Peng
X. F.
.
A fractal model for predicting the effective thermal conductivity of liquid with suspensions of nanoparticles
.
International Journal of Heat and Mass Transfer
,
46
:
2665
2672
,
2003
.
16.
Xuan
Y.
, and
Li
Q.
.
Heat transfer enhancement of nanofluids
.
International Journal of Heat and Fluid Flow
,
21
:
58
64
,
2000
.
17.
J. P. Hansen and I. R. McDonald. Theory of Simple Liquids. Academic Press, 1976
18.
R. Zwanzig. Nonequilibrium Statistical Mechanics. Oxford University Press, 2001.
19.
Russel
W. B.
.
Brownian motion of small particles suspended in liquids
.
Annual Review of Fluid Mechanics
,
12
:
425
455
,
1981
.
20.
Batchelor
G. K.
.
Brownian diffusion of particles with hydrodynamic interaction
.
Journal of Fluid Mechanics
,
74
:
1
29
,
1976
.
21.
Hamilton
R. L.
and
Crosser
O. K.
.
Thermal conductivity of heterogeneous two-component systems
.
I & EC Fundamentals
,
1
:
187
191
,
1962
.
This content is only available via PDF.
You do not currently have access to this content.