In order to investigate the possible effect of seismic vibration on two-phase flow dynamics and thermal-hydraulics of a nuclear reactor, experimental tests of adiabatic air-water two-phase flow under low-frequency vibration were carried out in this study. An eccentric cam vibration module operated at low motor speed (up to 390 rpm) was attached to an annulus test section which was scaled down from a prototypic boiling water reactor (BWR) fuel assembly subchannel. The inner and outer diameters of the annulus are 19.1 mm and 38.1 mm, respectively. The two-phase flow operating conditions cover the ranges of 0.03 m/s ≤ 〈jg〉 ≤ 1.46 m/s and 0.25 m/s ≤ 〈jf〉 ≤ 1.00 m/s and the vibration displacement ranges from ±0.8 mm to ±22.2 mm. Steady-state area-averaged instantaneous and time-averaged void fraction were recorded and analyzed in stationary and vibration experiments. A neural network flow regime identification technique and fast Fourier transformation (FFT) analysis were introduced to analyze the flow regimes and void signals under stationary and vibration conditions. Experimental results reveal possible changes in flow regimes under specific flow and vibration conditions. In addition, the instantaneous void fraction signals were affected and shown by FFT analysis. Possible reasons for the changes include the applied high acceleration and induced void/flow structure changes at certain ports under the specific flow and vibration conditions.

References

References
1.
Japan Business Press, August 21,
1993
.
2.
IAEA,
2011
, “
Fukushima Nuclear Accident Update Log
,” http://www.iaea.org/
3.
Chen
,
S. W.
,
Hibiki
,
T.
,
Ishii
,
M.
,
Mori
,
M.
, and
Watanabe
,
F.
,
2010
, “
Experimental Investigation of Vibration Effects on Subcooled Boiling Two-Phase Flow in an Annulus
,”
7th International Conference on Multiphase Flow (ICMF 2010)
,
Tampa, FL
, May 30–June 4.
4.
Nariai
,
H.
, and
Tanaka
,
T.
,
1994
, “
Void Fraction of Subcooled Flow Boiling Around Oscillating Heater Rod
,”
1994 Annual Spring Meeting of Atomic Energy Society of Japan
,
Univ. of Tsukuba
,
Tsukuba, Japan
, March 29–31, Paper No. J36.
5.
Hibiki
,
T.
and
Ishii
,
M.
,
1998
, “
Effect of Flow-Induced Vibration on Local Flow Parameters of Two-Phase Flow
,”
Nucl. Eng. Des.
,
185
, pp.
113
125
.10.1016/S0029-5493(98)00241-6
6.
Earthquake Lab
,
2004
, “
Introduction to Earthquake Waves
,” http://www.eq.ccu.edu.tw/∼ccusgm/seismography.htm
7.
USGS
,
2011
, “
Earthquake Facts
,” http://earthquake.usgs.gov/learn/facts.php
8.
Bolt
,
B. A.
,
1993
, “
Earthquake Intensity
,” http://www.eas.slu.edu/eqc/eqc_photos/mercalli.html
9.
Ministry of Energy, Mines and Petroleum Resources
,
2006
, “
How Big are Earthquakes?,
http://www.empr.gov.bc.ca/Mining/Geoscience/SurficialGeologyandHazards/Earthquakes/Pages/big.aspx
10.
Hong
,
S. S.
,
2006
, “
What are Magnitude and Intensity of an Earthquake?
http://www.ier.org.tw/html/newsletter/6/nl6-6.htm
11.
Situ
,
R.
,
Hibiki
,
T.
,
Sun
,
X.
,
Mi
,
Y.
, and
Ishii
,
M.
,
2004
, “
Flow Structure of Subcooled Boiling Flow in an Internally Heated Annulus
,”
Int. J. Heat Mass Transfer
,
47
, pp.
5351
5364
.10.1016/j.ijheatmasstransfer.2004.06.035
12.
Hibiki
,
T.
,
Situ
,
R.
,
Mi
,
Y.
, and
Ishii
,
M.
,
2003
, “
Local Flow Measurements of Vertical Upward Bubbly Flow in an Annulus
,”
Int. J. Heat Mass Transfer
,
46
, pp.
1479
1496
.10.1016/S0017-9310(02)00421-0
13.
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, Lemont, IL, Technical Paper No. ANL-77-47.
14.
Ozar
,
B.
,
Jeong
,
J. J.
,
Dixit
,
A.
,
Julia
,
J. E.
,
Hibiki
,
T.
, and
Ishii
,
M.
,
2008
, “
Flow Structure of Gas-Liquid Two-Phase Flow in an Annulus
,”
Chem. Eng. Sci.
,
63
, pp.
3998
4011
.10.1016/j.ces.2008.04.042
15.
Jones
,
O. C.
, and
Zuber
,
N.
,
1975
, “
Interrelation Between Void Fraction Fluctuations and Flow Patterns in Two-Phase Flow
,”
Int. J. Multiphase Flow
,
2
, pp.
273
306
.10.1016/0301-9322(75)90015-4
16.
Julia
,
J. E.
,
Liu
,
Y.
,
Paranjape
,
S.
, and
Ishii
,
M.
,
2008
, “
Upward Vertical Two-Phase Flow Local Flow Regime Identification Using Neural Network Techniques
,”
Nucl. Eng. Des.
,
238
, pp.
156
169
.10.1016/j.nucengdes.2007.05.005
17.
Lee
,
J. Y.
,
Ishii
,
M.
, and
Kim
,
N. S.
,
2008
, “
Instantaneous and Objective Flow Regime Identification Method for the Vertical Upward and Downward Co-Current Two-Phase Flow
,”
Int. J. Heat Mass Transfer
,
51
(
13–14
), pp.
3442
3459
.10.1016/j.ijheatmasstransfer.2007.10.037
18.
Paranjape
,
S.
,
Stefanczyk
,
D.
,
Liang
,
Y.
,
Hibiki
,
T.
, and
Ishii
,
M.
,
2008
, “
Global Flow Regime Identification in a Rod Bundle Geometry
,”
Proceedings of the 16th International Conference on Nuclear Engineering
,
Orlando, FL
, May 11–15, Paper No. ICONE16-48435.
19.
Paranjape
,
S.
,
Chen
,
S. W.
,
Hibiki
,
T.
, and
Ishii
,
M.
,
2011
, “
Flow Regime Identification Under Adiabatic Upward Two-Phase Flowing a Vertical Rod Bundle Geometry
,”
ASME Trans. J. Fluids Eng.
,
133
(
9
), p.
091302
.10.1115/1.4004836
20.
Julia
,
J. E.
,
Ozar
,
B.
,
Jeong
,
J. J.
,
Hibiki
,
T.
, and
Ishii
,
M.
,
2011
, “
Flow Regime Development Analysis in Adiabatic Upward Two-Phase Flow in a Vertical Annulus
,”
Int. J. Heat Fluid Flow
,
32
, pp.
164
175
.10.1016/j.ijheatfluidflow.2010.09.003
21.
Mi
,
Y.
,
Ishii
,
M.
, and
Tsoukalas
,
L. H.
,
1998
, “
Vertical Two-Phase Flow Identification Using Advanced Instrumentation and Neural Networks
,”
Nucl. Eng. Des.
,
184
, pp.
409
420
.10.1016/S0029-5493(98)00212-X
22.
Mi
,
Y.
,
Ishii
,
M.
, and
Tsoukalas
,
L. H.
,
2001
, “
Flow Regime Identification Methodology With Neural Networks and Two-Phase Flow Models
,”
Nucl. Eng. Des.
,
204
, pp.
87
100
.10.1016/S0029-5493(00)00325-3
23.
Mishima
,
K.
, and
Ishii
,
M.
,
1984
, “
Flow Regime Transition Criteria for Upward Two-Phase Flow in Vertical Tubes
,”
Int. J. Heat Mass Transfer
,
27
, pp.
723
737
.10.1016/0017-9310(84)90142-X
24.
Kelessidis
,
V. C.
, and
Dukler
,
A. E.
,
1989
, “
Modeling Flow Pattern Transitions for Upward Gas–Liquid Flow in Vertical Concentric and Eccentric Annuli
,”
Int. J. Multiphase Flow
,
15
, pp.
173
191
.10.1016/0301-9322(89)90069-4
25.
Das
,
G.
,
Das
,
P. K.
,
Purohit
,
N. K.
,
Mitra
,
A. K.
,
1999
, “
Flow Pattern Transition During Gas Liquid Upflow Through Vertical Concentric Annuli—Part II: Mechanistic Models
,”
ASME Trans. J. Fluids Eng.
,
121
, pp.
902
907
.10.1115/1.2823553
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