The clearance between fuel rods is maintained by spacer grid or helical wire wrap. Thermal-hydraulic characteristics inside fuel rod bundle are strongly influenced by the spacer grid geometry and the bundle pitch-to-diameter (P/D) ratio. This includes the maximum fuel temperature, critical heat flux, as well as pressure drop through the fuel bundle. An understanding of the detailed structure of flow mixing and heat transfer in a fuel rod bundle geometry is therefore an important aspect of reactor core design, both in terms of the reactor's safe and reliable operation, and with regard to optimum power extraction. In this study, computational fluid dynamics (CFD) simulations are performed to investigate isothermal turbulent flow mixing and heat transfer behavior in 4 × 4 rod bundle with twist-vane spacer grid with P/D ratio of 1.35. This work is carried out under International Atomic Energy Agency (IAEA) co-ordinated research project titled as “Application of Computational Fluid Dynamics (CFD) Codes for Nuclear Power Plant Design.” CFD simulations are performed using open source CFD code OpenFOAM. Numerical results are compared with experimental data from Korea Atomic Energy Research Institute (KAERI) and found to be in good agreement.

References

References
1.
Shen
,
Y. F.
,
Cao
,
Z. D.
, and
Liu
,
Q. G.
,
1991
, “
An Investigation of Crossflow Mixing Effect Caused by Grid Spacer With Mixing Blades in a Rod Bundle
,”
Nucl. Eng. Des.
,
125
(
2
), pp.
111
119
.
2.
Yang
,
S. K.
, and
Chung
,
M. K.
,
1996
, “
Spacer Grid Effects on Turbulent Flow in Rod Bundles
,”
Nuclear Eng. Technol.
,
28
(
1
), pp.
56
71
.
3.
McClusky
,
H. L.
,
Holloway
,
M. V.
,
Beasley
,
D. E.
, and
Conner
,
M. E.
,
2002
, “
Development of Swirling Flow in a Rod Bundle Subchannel
,”
ASME J. Fluids Eng.
,
124
(
3
), pp.
747
755
.
4.
Holloway
,
M. V.
,
McClusky
,
H. L.
,
Beasley
,
D. E.
, and
Conner
,
M. E.
,
2004
, “
The Effect of Support Grid Features on Local, Single-Phase Heat Transfer Measurements in Rod Bundles
,”
ASME J. Heat Transfer
,
126
(
1
), pp.
43
53
.
5.
Holloway
,
M. V.
,
Beasley
,
D. E.
, and
Conner
,
M. E.
,
2008
, “
Single-Phase Convective Heat Transfer in Rod Bundles
,”
Nucl. Eng. Des.
,
238
(
4
), pp.
848
858
.
6.
Chang
,
S. K.
,
Kim
,
S.
, and
Song
,
C. H.
,
2014
, “
Turbulent Mixing in a Rod Bundle With Vaned Spacer Grids: OECD/NEA-KAERI CFD Benchmark Exercise Test
,”
Nucl. Eng. Des.
,
279
, pp.
19
36
.
7.
Lee
,
J. R.
,
Kim
,
J.
, and
Song
,
C. H.
,
2014
, “
Synthesis of the Turbulent Mixing in a Rod Bundle With Vaned Spacer Grids Based on the OECD-KAERI CFD Benchmark Exercise
,”
Nucl. Eng. Des.
,
279
, pp.
3
18
.
8.
Shin
,
C. H.
,
Lee
,
C. Y.
, and
In
,
W. K.
,
2015
, “
IAEA Benchmark Specification and Experimental Data: Flow Mixing in a 4 × 4 Rod Bundle With a Mixing-Vane Spacer Grid
,” Korea Atomic Energy Research Institute, Daejeon, Korea, p.
55
.
9.
Lee
,
C. Y.
,
Shin
,
C. H.
, and
In
,
W. K.
,
2015
, “
IAEA Benchmark Specification and Experimental Data: Heat Transfer in a 4 × 4 Rod Bundle With a Mixing-Vane Grid
,” Korea Atomic Energy Research Institute, Daejeon, Korea, p.
38
.
10.
In
,
W. K.
,
Shin
,
C. H.
, and
Lee
,
C. Y.
,
2015
, “
Convective Heat Transfer Experiment of Rod Bundle Flow With Twist-Vane Spacer Grid
,”
Nucl. Eng. Des.
,
295
, pp.
173
181
.
11.
Lee
,
C. Y.
,
In
,
W. K.
, and
Lee
,
J. K.
,
2016
, “
Augmentation of Single-Phase Forced Convection Heat Transfer in Tightly Arrayed Rod Bundle With Twist-Vane Spacer Grid
,”
Exp. Therm. Fluid Sci.
,
76
, pp.
185
192
.
12.
In
,
W. K.
,
2001
, “
Numerical Study of Coolant Mixing Caused by the Flow Deflectors in a Nuclear Fuel Bundle
,”
Nucl. Technol.
,
134
(
2
), pp.
187
195
.
13.
Karoutas
,
Z.
,
GU
,
C. Y.
, and
Scholin
,
B.
,
1995
, “
3-D Flow Analyses for Design of Nuclear Fuel Spacer
,”
Seventh International Meeting on Nuclear Reactor Thermal-Hydraulics (NURETH-7)
, Saratoga Springs, New York, Sept. 10–15, pp.
3153
3175
.
14.
Smith
,
L. D.
, III
,
Conner
,
M. E.
,
Liu
,
B.
,
Dzodzo
,
M. B.
,
Paramonov
,
D. V.
,
Beasley
,
D. E.
,
Langford
,
H. M.
, and
Holloway
,
M. V.
,
2002
, “
Benchmarking Computational Fluid Dynamics for Application to PWR Fuel
,”
ASME
Paper No. ICONE10-22475.
15.
Langford
,
H. M.
,
Armfield
,
M. V.
,
Beasley
,
D. E.
, and
Conner
,
M. E.
,
2001
, “
Particle Image Velocimetry of Swirling Flow in a Subchannel of a Rod Bundle
,”
ASME Paper No. FEDSM2001-18007
.
16.
Armfield
,
M. V.
,
Langford
,
H. M.
,
Beasley
,
D. E.
, and
Conner
,
M. E.
,
2001
, “
Single-Phase Turbulent Rod Bundle Heat Transfer
,”
ASME International Mechanical Engineering Congress and Exposition, New York, Nov. 11–16, pp. 153–164
.
17.
Conner
,
M. E.
,
Baglietto
,
E.
, and
Elmahdi
,
A. M.
,
2010
, “
CFD Methodology and Validation for Single-Phase Flow in PWR Fuel Assemblies
,”
Nucl. Eng. Des.
,
240
(
9
), pp.
2088
2095
.
18.
Holloway
,
M. V.
,
Conover
,
T. A.
,
McClusky
,
H. L.
,
Beasley
,
D. E.
, and
Conner
,
M. E.
,
2005
, “
The Effect of Support Grid Design on Azimuthal Variation in Heat Transfer Coefficient for Rod Bundles
,”
ASME J. Heat Transfer
,
127
(
6
), pp.
598
605
.
19.
Liu
,
C. C.
, and
Ferng
,
Y. M.
,
2010
, “
Numerically Simulating the Thermal-Hydraulic Characteristics Within the Fuel Rod Bundle Using CFD Methodology
,”
Nucl. Eng. Des.
,
240
(
10
), pp.
3078
3086
.
20.
Gandhir
,
A.
, and
Hassan
,
Y.
,
2011
, “
RANS Modeling for Flow in Nuclear Fuel Bundle in Pressurized Water Reactors (PWR)
,”
Nucl. Eng. Des.
,
241
(
11
), pp.
4404
4408
.
21.
Liu
,
C. C.
,
Ferng
,
Y. M.
, and
Shih
,
C. K.
,
2012
, “
CFD Evaluation of Turbulence Models for Flow Simulation of the Fuel Rod Bundle With a Spacer Assembly
,”
Appl. Therm. Eng.
,
40
, pp.
389
396
.
22.
Podila
,
K.
,
Rao
,
Y. F.
,
Krause
,
M.
, and
Bailey
,
J.
,
2014
, “
A CFD Simulation of 5 × 5 Rod Bundle With Split-Type Spacers
,”
Prog. Nucl. Energy
,
70
, pp.
167
175
.
23.
Tseng
,
Y. S.
,
Ferng
,
Y. M.
, and
Lin
,
C. H.
,
2014
, “
Investigating Flow and Heat Transfer Characteristics in a Fuel Bundle With Split-Vane Pair Grids by CFD Methodology
,”
Ann. Nucl. Energy
,
64
, pp.
93
99
.
24.
Podila
,
K.
, and
Rao
,
Y.
,
2016
, “
CFD Modelling of Turbulent Flows Through 5 × 5 Fuel Rod Bundles With Spacer-Grids
,”
Ann. Nucl. Energy
,
97
, pp.
86
95
.
25.
OpenFOAM
,
2013
, “
User Guide to OpenFOAM 2.2.2
,” The OpenFOAM Foundation, London, accessed Nov. 10, 2017, www.openfoam.org
26.
Menter
,
F. R.
,
1994
, “
Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications
,”
AIAA J.
,
32
(
8
), pp.
1598
1605
.
27.
Patankar
,
S. V.
,
1980
,
Numerical Heat Transfer and Fluid Flow
,
Hemisphere Publishing Corporation/Taylor & Francis Group
,
New York
, pp.
126
131
.
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