For narrow space boiling, it is difficult to release bubbles from the narrow space, especially on a large-area surface. To solve this problem, a new structure is designed in the present paper. An experimental study of pool boiling on the novel copper enhanced structure, with the separate ordinary confined spaces and the open channels between them, was conducted with water and ethanol. High-speed visualizations are performed to elucidate the bubble flow. The results show that the boiling performance of both water and ethanol can be enhanced effectively. The visualizations indicated that most active nucleation sites emerged in the confined channels and rarely appeared at the bare surfaces not covered by enhanced structures even at high superheat. The bubble diameter, the bubble departure frequency, and the numbers of nucleation sites are obtained using statistical methods. The results suggest that the magnitudes of bubble diameter of water are almost the same on the smooth and enhanced surfaces. The amount of nucleation sites on the enhanced surfaces is remarkably increased, indicating its key role in the boiling enhancement of water. The bubble departure frequency is increased on one of the enhanced surfaces while not increased on another, showing that it is also a significant factor for heat transfer enhancement under certain conditions. While for ethanol, all the three parameters are increased on the enhanced surfaces.

References

1.
Jakob
,
M.
, 1949,
Heat Transfer
,
Wiley
,
New York
, pp.
636
638
.
2.
McHale
,
J. P.
, and
Garimella
,
S. V.
, 2010, “
Bubble Nucleation Characteristics in Pool Boiling of a Wetting Liquid on Smooth and Rough Surfaces
,”
Int. J. Multiphase Flow
,
36
, pp.
249
260
.
3.
Misale
,
M.
,
Guglielmini
,
G.
, and
Priarone
,
A.
, 2009, “
HFE-7100 Pool Boiling Heat Transfer and Critical Heat Flux in Inclined Narrow Spaces
,”
Int. J. Refrig.
,
32
, pp.
235
245
.
4.
Stephan
,
P.
, and
Kern
,
J.
, 2004, “
Evaluation of Heat and Mass Transfer Phenomena in Nucleate Boiling
,”
Int. J. Heat Fluid Flow
,
25
, pp.
140
148
.
5.
Pastuszko
,
R.
, 2008, “
Boiling Heat Transfer Enhancement in Subsurface Horizontal and Vertical Tunnels
,”
Exp. Therm. Fluid Sci.
,
32
, pp.
1564
1577
.
6.
Webb
,
R. L.
, 2004, “
Odyssey of the Enhanced Boiling Surface
,”
ASME Trans. J. Heat Transfer
,
126
, pp.
1051
1059
.
7.
Das
,
A. K.
,
Das
,
P. K.
, and
Saha
,
P.
, 2009, “
Performance of Different Structured Surfaces in Nucleate Pool Boiling
,”
Appl. Therm. Eng.
,
29
, pp.
3643
3653
.
8.
Li
,
C.
,
Wang
,
Z.
,
Wang
,
P.
,
Peles
,
Y.
,
Koratkar
,
N.
, and
Peterson
,
G. P.
, 2008,
Nanostructured Copper Interfaces for Enhanced Boiling
, Vol.
8
,
Wiley-VCH Verlag GmbH & Co. KGaA
,
Weinheim
, pp.
1084
1088
.
9.
Li
,
S. H.
,
Furberg
,
R.
,
Toprak
,
M. S.
,
Palm
,
B.
, and
Muhammed
,
M.
, 2008, “
Nature-Inspired Boiling Enhancement by Novel Nanostructured Macroporous Surfaces
,”
Adv. Funct. Mater.
,
18
, pp.
2215
2220
.
10.
Kim
,
J. H.
,
Rainey
,
K. N.
,
You
,
S. M.
, and
Pak
,
J. Y.
, 2002, “
Mechanism of Nucleate Boiling Heat Transfer Enhancement From Microporous Surface in Saturated FC 72
,”
ASME Trans. J. Heat Transfer
,
124
, pp.
500
506
.
11.
Ishibashi
,
E.
, and
Nishikawa
,
K.
, 1969, “
Saturated Boiling Heat Transfer in Narrow Spaces
,”
Int. J. Heat Mass Transfer
,
12
, pp.
863
894
.
12.
Xia
,
C. L.
,
Hu
,
W. L.
, and
Guo
,
Z. Y.
, 1996, “
Natural Convective Boiling in Vertical Rectangular Narrow Channels
,”
Exp. Therm. Fluid Sci.
,
12
, pp.
313
324
.
13.
Zhao
,
Y. H.
,
Tsuruta
,
T.
, and
Ji
,
C. Y.
, 2003, “
Experimental Study of Nucleate Boiling Heat Transfer Enhancement in Confined Space
,”
Exp. Therm. Fluid Sci.
,
28
, pp.
9
16
.
14.
Passos
,
J. C.
,
Possamai
,
L. F. B.
, and
Hirata
,
F. R.
, 2005, “
Confined and Unconfined FC72 and FC87 Boiling on a Downward-Facing Disc
,”
Appl. Therm. Eng.
,
25
, pp.
2543
2554
.
15.
Ghiu
,
C. D.
, and
Joshi
,
Y. K.
, 2006, “
Pool Boiling Using Thin Enhanced Structures Under Top-Confined Conditions
,”
ASME Trans. J. Heat Transfer
,
128
, pp.
1302
1311
.
16.
Rops
,
C. M.
,
Lindken
,
R.
,
Velthuis
,
J. F. M.
, and
Westerweel
,
J.
, 2009, “
Enhanced Heat Transfer in Confined Pool Boiling
,”
Int. J. Heat Fluid Flow
,
30
, pp.
751
760
.
17.
Kandlikar
,
S. G.
, 2001, “
A Theoretical Model to Predict Pool Boiling CHF Incorporating Effects of Contact Angle and Orientation
,”
ASME Trans. J. Heat Transfer
,
123
, pp.
1071
1079
.
18.
Cheng
,
P.
,
Wu
,
H. Y.
, and
Hong
,
F. J.
, 2007, “
Phase-Change Heat Transfer in Microsystems
,”
ASME Trans. J. Heat Transfer
,
129
, pp.
101
107
.
19.
Bang
,
I. C.
, and
Chang
,
S. H.
, 2005, “
Boiling Heat Transfer Performance and Phenomena of Al2O3-Water Nano-Fluids From a Smooth Surface in a Pool
,”
Int. J. Heat Mass Transfer
,
48
, pp.
2407
2419
.
20.
Mikic
,
B. B.
, and
Rohsenow
,
W. M.
, 1969, “
A New Correlation of Pool Boiling Data Including the Effect of Heating Surface Characteristics
,”
ASME Trans. J. Heat Transfer
,
91
, pp.
245
250
.
21.
Pioro
,
I. L.
, 1999, “
Experimental Evaluation of Constants for the Rohsenow Pool Boiling Correlation
,”
Int. J. Heat Mass Transfer
,
42
, pp.
2003
2013
.
22.
Bergles
,
A. E.
, 1997, “
Enhancement of Pool Boiling
,”
Int. J. Refrig.
,
20
, pp.
545
551
.
23.
Prasad
,
L.
,
Alam
,
M. S.
,
Gupta
,
S. C.
, and
Agarwal
,
V. K.
, 2007, “
Enhanced Boiling of Methanol on Copper Coated Surface
,”
Chem. Eng. Technol.
,
30
, pp.
901
906
.
24.
Judd
,
R. L.
, and
Hwang
,
K. S.
, 1976, “
A Comprehensive Model for Nucleate Boiling Heat Transfer Including Microlayer Evaporation
,”
ASME Trans. J. Heat Transfer
,
98
, pp.
623
629
.
25.
Haider
,
S. I.
, and
Webb
,
R. L.
, 1997, “
A Transient Micro-Convection Model of Nucleate
,”
Int. J. Heat Mass Transfer
,
40
, pp.
3675
3688
.
26.
Phan
,
H. T.
,
Caney
,
N.
,
Marty
,
P.
,
Colasson
,
S.
, and
Gavillet
,
J.
, 2009, “
Surface Wettability Control by Nanocoating: The Effects on Pool Boiling Heat Transfer and Nucleation Mechanism
,”
Int. J. Heat Mass Transfer
,
52
, pp.
5459
5471
.
27.
Plawsky
,
J. L.
,
Ojha
,
M.
,
Chatterjee
,
A.
, and
Wayner
,
P. C.
, 2007, “
Enhancing Transport Processes by Controlling Contact Line Dynamics
,”
The Eighteenth International Symposium on Transport Phenomena
, Daejeon, Korea, Aug. 27–30, pp.
123
130
.
28.
Webb
,
R. L.
, 1981, “
The Evolution of Enhanced Surface Geometries for Nucleate Boiling
,”
Heat Transfer Eng.
,
2
, pp.
46
69
.
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