While there has been much previous research on the thermal conductivity and convection performance of nanofluids, these data are rarely reported together with effective viscosity data that govern the relevance for heat exchanger applications. We report here the effective convection coefficient and viscosity in microtubes (D=0.5mm) along with stationary thermal conductivity measurements for nanofluids based on spherical particles (Al2O3, ZnO, and CuO) and carbon nanotubes. Sample data include an effective convection coefficient increase of 5% for 3vol%Al2O3/DI water nanofluid, 13.3% for 4vol% CuO/DI water nanofluid, and 11.6% for 0.2vol% Carbon nanotube(CNT)/DI water nanofluid. When considered together with our viscosity measurement on the same fluids, we find that the only the CNT-based nanofluids are promising for microfluidic heat exchangers.

1.
Prasher
,
R. P.
,
Song
,
D.
,
Wang
,
J.
, and
Phelan
,
P.
, 2006, “
Measurements of Nanofluid Viscosity and Its Implications for Thermal Applications
,”
Appl. Phys. Lett.
0003-6951,
89
, p.
133108
.
2.
Eastman
,
J. A.
,
Choi
,
U. S.
,
Li
,
S.
,
Thompson
,
L. J.
, and
Lee
,
S.
, 1996, “
Enhanced Thermal Conductivity Through the Development of Nanofluids
,”
Proceedings of Materials Research Society Symposium
, Boston, MA, Dec. 2–5, Vol.
457
, pp.
3
11
.
3.
Kabelac
,
S.
, and
Kuhnke
,
J. F.
, 2006, “
Heat Transfer Mechanisms in Nanofluids—Experiments and Theory
,”
Annals of the Assembly for International Heat Transfer Conference 13
.
4.
Wen
,
D.
, and
Ding
,
Y.
, 2004, “
Effective Thermal Conductivity of Aqueous Suspensions of Carbon Nanotubes(Carbon Nanotube Nanofluids)
,”
J. Thermophys. Heat Transfer
0887-8722,
18
(
4
), pp.
481
485
.
5.
Zhang
,
X.
,
Gu
,
H.
, and
Fujii
,
M.
, 2006, “
Effective Thermal Conductivity and Thermal Diffusivity of Nanofluids Containing Spherical and Cylindrical Nanoparticles
,”
J. Appl. Phys.
0021-8979,
100
, p.
044325
.
6.
Chon
,
C.
,
Kihm
,
K.
,
Lee
,
S.
, and
Choi
,
S.
, 2005, “
Empirical Correlation Finding the Role of Temperature and Particle Size for Nanofluid (Al2O3) Thermal Conductivity Enhancement
,”
Appl. Phys. Lett.
0003-6951,
87
, p.
153107
.
7.
Xuan
,
Y.
, and
Li
,
Q.
, 2003, “
Investigation on Convective Heat Transfer and Flow Features of Nanofluids
,”
ASME J. Heat Transfer
0022-1481,
125
, pp.
151
155
.
8.
Wen
,
D.
, and
Ding
,
Y.
, 2004, “
Experimental Investigation Into Convective Heat Transfer of Nanofluids at the Entrance Region Under Laminar Flow Conditions
,”
Int. J. Heat Mass Transfer
0017-9310,
47
, pp.
5181
5188
.
9.
Ding
,
Y.
,
Alias
,
H.
,
Wen
,
D.
, and
Williams
,
R. A.
, 2006, “
Heat Transfer of Aqueous Suspensions of Carbon Nanotubes
,”
Int. J. Heat Mass Transfer
0017-9310,
49
, pp.
240
250
.
10.
Lee
,
J.
, and
Mudawar
,
I.
, 2007, “
Assessment of the Effectiveness of Nanofluids for Single-Phase and Two-Phase Heat Transfer in Micro-Channels
,”
Int. J. Heat Mass Transfer
0017-9310,
50
, pp.
452
463
.
11.
Rea
,
U.
,
McKrell
,
T.
,
Hu
,
L.
, and
Buongiorno
,
J.
, 2009, “
Laminar Convective Heat Transfer and Viscous Pressure Loss of Alumina-Water and Zirconia-Water Nanofluids
,”
Int. J. Heat Mass Transfer
0017-9310,
52
, pp.
2042
2048
.
12.
Williams
,
W.
,
Buongiorno
,
J.
, and
Hu
,
L.
, 2008, “
Experimental Investigation of Turbulent Convective Heat Transfer and Pressure Loss of Alumina/Water and Zirconia/Water Nanoparticle Colloids (Nanofluids) in Horizontal Tubes
,”
ASME J. Heat Transfer
0022-1481,
130
, p.
042412
.
13.
Churchill
,
S. W.
, and
Chu
,
H. H. S.
, 1975, “
Correlating Equations for Laminar and Turbulent Free Convection From a Horizontal Cylinder
,”
Int. J. Heat Mass Transfer
0017-9310,
18
, pp.
1049
1053
.
14.
White
,
F. M.
, 1991,
Viscous Fluid Flow
, 2nd ed.,
McGraw-Hill
,
New York
.
15.
Batchelor
,
G. K.
, 1977, “
The Effect of Brownian Motion on the Bulk Stress in a Suspension of Spherical Particles
,”
J. Fluid Mech.
0022-1120,
83
, pp.
97
117
.
16.
Gharagozloo
,
P. E.
,
Eaton
,
J. K.
, and
Goodson
,
K. E.
, 2008, “
Diffusion, Aggregation, and the Thermal Conductivity of Nanofluids
,”
Appl. Phys. Lett.
0003-6951,
93
, p.
103110
.
17.
Gharagozloo
,
P. E.
,
Eaton
,
J. K.
, and
Goodson
,
K. E.
, 2007, “
Impact of Thermodiffusion on Temperature Fields in Stationary Nanofluids
,”
Proceedings of ASME Interpack
, Vancouver, BC, Canada, Jul. 8–12.
18.
Kolade
,
B.
,
Goodson
,
K. E.
, and
Eaton
,
J. K.
, 2009, “
Convective Performance of Nanofluids in a Laminar Thermally Developing Tube Flow
,”
ASME J. Heat Transfer
0022-1481,
131
(
5
), p.
052402
.
You do not currently have access to this content.