The vertical co-current downward air-water two-phase flow was studied under adiabatic condition in round tube test sections of 25.4-mm and 50.8-mm ID. In flow regime identification, a new approach was employed to minimize the subjective judgment. It was found that the flow regimes in the co-current downward flow strongly depend on the channel size. In addition, various local two-phase flow parameters were acquired by the multi-sensor miniaturized conductivity probe in bubbly flow. Furthermore, the area-averaged data acquired by the impedance void meter were analyzed using the drift flux model. Three different distributions parameters were developed for different ranges of non-dimensional superficial velocity, defined by the ration of total superficial velocity to the drift velocity.

1.
Oshinowo
,
T.
, and
Charles
,
M. E.
,
1974
, “
Vertical two-phase flow Part I. Flow pattern correlation
,”
Can. J. Chem. Eng.
,
52
, pp.
25
35
.
2.
Barnea
,
D.
,
Shoham
,
O.
, and
Taitel
,
Y.
,
1982
, “
Flow pattern transition for vertical downward two phase flow
,”
Chem. Eng. Sci.
,
37
(
5
), pp.
741
744
.
3.
Yamaguchi
,
K.
, and
Yamazaki
,
Y.
,
1984
, “
Combinated flow pattern map for cocurrent and countercurrent air-water flows in vertical tube
,”
J. Nucl. Sci. Technol.
,
21
(
5
), pp.
321
327
.
4.
Usui
,
K.
, and
Sato
,
K.
,
1989
, “
Vertically downward two-phase flow, (I) Void distribution and average void fraction
,”
J. Nucl. Sci. Technol.
,
26
(
7
), pp.
670
680
.
5.
Mi, Y., 1998, “Two-phase flow characterization base on advanced instrumentation, neural networks, and mathematical modeling,” Ph.D. Thesis, Purdue University, West Lafayette, IN, USA.
6.
Kim
,
S.
,
Fu
,
X. Y.
,
Wang
,
X.
, and
Ishii
,
M.
,
2000
, “
Development of the miniaturized four-sensor conductivity probe and the signal processing scheme
,”
J. Heat Transfer
,
43
, pp.
4101
4118
.
7.
Wu
,
Q.
, and
Ishii
,
M.
,
1999
, “
Sensitivity study on double-sensor conductivity probe for the measurement of interfacial area concentration in bubbly flow
,”
Int. J. Multiphase Flow
,
25
(
1
), pp.
155
173
.
8.
Wang
,
S. K.
,
Lee
,
S. J.
,
Jones
, Jr,
O. C.
, and
Lahey
, Jr.,
R. T.
,
1987
, “
3-D Turbulence structure and phase distribution measurements in bubbly two-phase flows
,”
Int. J. Multiphase Flow
,
13
, pp.
327
343
.
9.
Kashinsky
,
O. N.
, and
Randin
,
V. V.
,
1999
, “
Downward bubbly gas-liquid flow in a vertical pipe
,”
Nucl. Eng. Des.
,
25
, pp.
109
138
.
10.
Hibiki
,
T.
,
Hogsett
,
S.
, and
Ishii
,
M.
,
1998
, “
Local measurement of interfacial area, interfacial velocity and liquid turbulence in two-phase flow
,”
Nucl. Eng. Des.
,
184
(
2–3
), pp.
287
304
.
11.
Kocamustafaogullari
,
G.
, and
Ishii
,
M.
,
1995
, “
Foundations of the interfacial area transport equation and its closure relations
,”
Int. J. Heat Mass Transfer
,
38
(
3
), pp.
481
493
.
12.
Wu
,
Q.
,
Kim
,
S.
,
Ishii
,
M.
, and
Beus
,
S. G.
,
1998
, “
One-group interfacial area transport in vertical bubbly flow
,”
Int. J. Heat Mass Transfer
,
41
(
8–9
), pp.
1103
1112
.
13.
Kim, S., 1999, “Interfacial area transport equation and measurement of local interfacial characteristics,” Ph.D. Thesis, Purdue University, West Lafayette, IN, USA.
14.
Sun, X., 2001, “Two-group interfacial area transport equation for a confined test section,” Ph.D. Thesis, Purdue University, West Lafayette, IN, USA.
15.
Zuber
,
N.
, and
Findlay
,
J. A.
,
1965
, “
Average volumetric concentration in two-phase flow systems
,”
ASME J. Heat Transfer
,
87
, pp.
453
468
.
16.
Hirao, Y., Kawanishi, K., and Tsuge, A. and Kohriyama, T., 1986, “Experimental study on drift flux correlation formulas for two-phase flow in large diameter tubes,” Proceedings of second international topical meeting on nuclear power plant thermal hydraulics and operations, pp. 1-88-1-94.
17.
Kawanishi
,
K.
,
Hirao
,
Y.
, and
Tsuge
,
A.
,
1990
, “
An experimental study on drift flux parameters for two-phase flow in vertical round tubes
,”
Nucl. Eng. Des.
,
120
, pp.
447
458
.
18.
Ishii, M., 1977, “One-dimensional drift-flux model and constitutive equations for relative motion between phases in various two-phase flow regimes,” Argonne National Laboratory Report ANL-77-47.
19.
Goda, H, 2001, “Flow regimes and local parameter measurements for downward two-phase flow,” MS Thesis, School of Nuclear Engineering, Purdue University, West Lafayette, IN, USA.
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