To investigate the characteristics of CHF (Critical Heat Flux) enhancement using nano-fluids, pool boiling CHF experiments of two water-based nano-fluids with titania and alumina nanoparticles were performed using electrically heated metal wires under atmospheric pressure. The results showed that the water-based nano-fluids significantly enhanced CHF compared to that of pure water. SEM (Scanning Electron Microscopy) observation subsequent to the pool boiling experiments revealed that a lot of nanoparticles were deposited on heating surface during pool boiling of nano-fluids. In order to investigate the role of the nanoparticle surface coating on CHF enhancement of nano-fluids, pool boiling CHF of pure water was measured using a nanoparticle-coated heater prepared by pool boiling of nanofluids on a bare heater. It was found that pool boiling of pure water on the naonoparticle-coated heater sufficiently achieved the CHF enhancement of nano-fluids. It is supposed that CHF enhancement in pool boiling of nano-fluids is mainly caused by the nanoparticle coating of the heating surface. 2006 Elsevier Ltd. All rights reserved.
[1]
P. F. Vassallo,et al.
Pool boiling heat transfer experiments in silica–water nano-fluids
,
2004
.
[2]
Soon-Heung Chang,et al.
Boiling heat transfer performance and phenomena of Al2O 3-water nano-fluids from a plain surface in a pool
,
2004
.
[3]
J. H. Kim,et al.
Effect of nanoparticles on critical heat flux of water in pool boiling heat transfer
,
2003
.
[4]
I. Golobič,et al.
The role of enhanced coated surface in pool boiling CHF in FC-72
,
2000
.
[5]
S. M. You,et al.
Enhanced boiling heat transfer from microporous surfaces: effects of a coating composition and method
,
1997
.
[6]
M. Kaviany,et al.
Pool-boiling CHF enhancement by modulated porous-layer coating: theory and experiment
,
2001
.
[7]
M. Osakabe,et al.
The effect of fouling on nucleate pool boiling of small wires
,
2004
.