HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
C. H. Pyeon, T. Misawa, H. Unesaki, K. Mishima and S. Shiroya
(Kyoto University Research Reactor Institute, Japan)
Benchmark Experiments of Accelerator Driven Systems (ADS) in
Kyoto University Critical Assembly (KUCA)
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Contents
Background and PurposeA plan of ADSR (Kart & Lab. Project):Accelerator Driven Subcritical Reactor (ADSR) in Kyoto University Critical Assembly (KUCA) by using Fixed Field Alternating Gradient (FFAG) Accelerator
Neutron spectrum experiments by Foil activation method- 14MeV neutron experiment (Pulsed neutron generator)- High-energy proton experiment (FFAG accelerator)ADS collaboration research in Japan
IAEA benchmark problem
Summary
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Background
ADS Research and Development:
producing energy and transmuting minor actinides
and long-lived fission products
A neutron source in next generation of KURRI andintroduction of a new accelerator
Injection of 150MeV proton beam into KUCA core (with Tungsten (W) target) on Aug. 2007
Investigation of main characteristics of ADSR using KUCA core with 14MeV pulsed neutrons generator
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Purpose
Conduct feasibility study of ADSR in KURRI as Energy Amplifier System
Examine subcritical neutronic characteristics through experiments in KUCA (KUCA A core + 14MeV pulsed neutron generator)
Assess neutronic characteristics for 14MeV neutrons by MCNP analyses with nuclear data libraries
Establish measurement techniques- Reaction rate distribution, Neutron spectrum, etc.- Subcriticality, Neutron multiplication, Neutron decay constant
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
FFAG Accelerator
Main parameters in the FFAG accelerator
# of sectors 12 Energy 2.5 - 150MeV Repetition rate 120Hz Average beam current 1nA Rf frequency 1.5 - 4.6MHz Field index 7.5 Closed orbit radius 4.4 - 5.3m
Ion Generator
Ion Beta(FFAG Acc.) Main Ring
(FFAG Acc.)
KUCABooster
(FFAG ACC.)
100keV 2.5MeV 20MeV 150MeV
H+
Max. Power : 100WYield : 1 ×1010 n/s
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
KUCA A-core & FFAG Accelerator
KUCA A coreBeam LineFFAG Accelerator
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
KUCA A-core & 14MeV D-T Accelerator
KUCA A-core
Cockcroft-Walton type Accelerator
Accelerator (D-T reactions)
TritiumTarget
- 14MeV Pulsed Neutrons- Yield: 1×109 n/s, Intensity: 0.5mA
Critical Assembly- Highly enriched 235U- Polyethylene Reflector & Moderator- Thermal neutron field
Accelerator (D-T reactions)- 14MeV Pulsed Neutrons- Yield: 1×109 n/s, Intensity: 0.5mA
Critical Assembly- Highly enriched 235U- Polyethylene Reflector & Moderator- Thermal neutron field
BeamInjection
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
KUCA A-core (with Neutron guide)
Fig. Image of KUCA A-core and fuel assembly loaded
53.8cm
39.5cm
59.1cm
0.63cm(1/4")Polyethylene
0.3086cm(1/8")Polyethylene
0.15874cm(1/16")Enriched Uranium
152.4cm
Fuel Cell×36
Polyethylene
Fuelassembly
Aluminumsheath
Collimatorregion
Polyethylene
- KUCA A-core -A solid-moderated and reflected core
Fig. KUCA A-core with neutron guide
F F F F F
F F F F F
F F SV F F
F F SV F F
22 SV 22
s'
s s s
s s s
b bs bs bs b
b bs bs bs b
f fs fs fs f
C3 S5
S4 C1
C2 S6
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Neutron Spectrum Experiments by 14MeV Neutrons
Fig. KUCA A-core with neutron guide
F F F F F
F F F F F
F F SV F F
F F SV F F
22 SV 22
s'
s s s
s s s
b bs bs bs b
b bs bs bs b
f fs fs fs f
C3 S5
S4 C1
C2 S6
Irradiation- Positions: Core center and Target- Method: Foil activation method - Irradiation time: 3 to 6 hrsSubcriticality- 0.87, 1.23, 1.75%Δk/kMCNP-4C2 and ENDF/B-VI.2
Irradiation- Positions: Core center and Target- Method: Foil activation method - Irradiation time: 3 to 6 hrsSubcriticality- 0.87, 1.23, 1.75%Δk/kMCNP-4C2 and ENDF/B-VI.2
Reaction Threshold[MeV]
Size[mm3]
115In (n, n’) 115mIn 0.32
2.97
3.2592Nb (n, 2n) 92mNb 9.05 45×45×2
Normalization
56Fe (n, p) 56Mn
45×45×3
45×45×5
45×45×527Al (n, α) 24Na
1φ×0.05197Au (n, γ) 198Au
Table Activation foils with threshold energy and size
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Reaction Rates Evaluation
Core Threshold[MeV]
C/E (0.87%Δk/k)
C/E (1.23%Δk/k)
C/E(1.75%Δk/k)
0.32 2.10 ± 0.05
0.20 ± 0.01
0.92 ± 0.03
None
2.97
3.25
115In
9.05
2.31 ± 0.05
0.14 ± 0.01
1.10 ± 0.03
None
2.22 ± 0.0556Fe 0.17 ± 0.0127Al 1.05 ± 0.0393Nb 0.10 ± 0.01
Table Comparison of measured reaction rates with calculated ones
Target C/E115In 4.50 ±
0.13 0.88 ±0.02 1.26 ±0.04
56Fe27Al93Nb 1.29 ±
0.04
Reaction rates evaluation
Good: 27Al within 10% error regardless of subcriticalityLarge discrepancy: 115In, 56Fe and 93NbRelationship between C/E value and subcriticality
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Unfolding Evaluation
10-1 100 10110-5
10-4
10-3
10-2
10-1
100
101
Energy [MeV]
Neu
tron
flux
[Arb
trary
uni
ts]
ρ = 1.23 %Δk/k
Unfolding (SANDII)
Initial guess (MCNP)
Fig. Comparison of unfolding with initial guess
Numerical analyses
- Unfolding by SANDII (based on measured reaction rates)
- Initial guess by MCNP (ENDF/B-VI.2)
Good evaluation by unfolding analyses based on measured reaction rates
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Neutron Spectrum Experiments at FFAG accelerator
50 mm
W (t = 3mm)
Nb (t = 1mm)
Bi (t = 3mm)
500mm
750mm
Beam duct 500mm
540mm
200mm
Flange
25mm
Proton beam
Proton beam (At beam dump: 70MeV, 0.4n)184W target and 93Nb (Norm. factor of neutron generation) 209Bi Threshold Energy (15 to 90MeV): 209Bi (n, xn) 210-xBi (x=3 to 12)
Fig. Top view of PoP FFAG acc. (KEK)
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Neutrons and Protons Estimation
Reaction Threshold[MeV]
Measured reaction rate
209Bi (n,3n) 207Bi 14.42
22.55
29.62
38.13
45.37
54.24
61.69
70.89
78.47
87.94
-
209Bi (n,4n) 206Bi (1.51 ± 0.01) ×105
209Bi (n,5n) 205Bi (1.01 ± 0.03) ×105
209Bi (n,6n) 204Bi (2.37 ± 0.02) ×104
209Bi (n,7n) 203Bi (6.35 ± 0.16) ×103
209Bi (n,8n) 202Bi (2.74 ± 0.07) ×102
209Bi (n,9n) 201Bi -
209Bi (n,10n) 200Bi -
209Bi (n,11n) 199Bi -
209Bi (n,12n) 198Bi -
Table Measured reaction rates obtained at FFAG acc.
10-3 10-2 10-1 100 101 10210-7
10-6
10-5
10-4
10-3
10-2
Neutron energy [MeV]
Neu
tron
flux
[Arb
itrar
y un
its]
Proton beam injection
70MeV
80MeV
100MeV
Fig. Calculated neutron spectrum evaluated by MCNPX
About 60MeV neutron generation by about 70MeV proton injection onto 184WUseful foil of 209Bi covering wide rangeof threshold energy
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
KURRI (Kart & Lab. project): KUCA, FFAG Accelerator Thermal neutron field → Energy amplifier system
JAEA (J-PARC project): FCA, TEF-P, TEF-TFast neutron field → Nuclear Transmutation
User and support group: Tohoku Univ., Nagoya Univ., Kinki Univ., etc.
Subcriticality measurement (Noise method, NSM method, etc.)Neutronic characteristics (Neutron flux, Neutron spectrum, etc.)Nuclear Transmutation (MAs, FPs, etc.)
ADSR neutronsource (Thermal)
KUCA (Thermal)FFAG Acc. (1Gev)
KUCA (Thermal)FFAG Acc. (150Mev)
ADS TestReactor (Fast)
TEF-P TEF-TJ-PARC
LINAC 800MeV
FCA
ADSIncineration (Fast)
KURRI JAEA
ADS Collaboration Research in Japan
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Phase I: Static experiments (14MeV neutrons)
Reaction rates distribution, Neutron spectrum, Reactivity
Phase II: Kinetic experiments (14MeV neutrons)
Neutron multiplication, Subcriticality measurement method(Rossi-α, Feynman-α, Pulsed neutrons and
Neutron source multiplication (NSM) methods)Phase III: Static and Dynamic experiments (150MeV protons)
Above topics, γ-ray distribution, Power monitoring, etc.
- Fuel: Highly enriched 235U, 232Th, Natural Uranium- Reflector: Polyethylene, Graphite, Aluminum, Beryllium - Core: Any combinations of Fuel & Reflector
Publish KUCA benchmark problem in a near future
IAEA Benchmark Problem
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
ADSR project (Kart & Lab. project) in KURRI
- Energy amplifier system by ADSR
Neutron spectrum experiments of ADSR
- 14MeV pulsed neutrons in KUCA
・ Reaction rates evaluation: Good results by foil activation method
・ Unfolding evaluation: Feasibility of SANDII code
- High-energy protons from FFAG accelerator
・ About 60MeV neutron generation by about 70MeV proton
injection onto 184W target
・ Useful activation foil of 209Bi covering wide range of threshold
From 14MeV neutron results, very important and valuable
information, for 150MeV proton analyses
Summary
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
KUCA A-core
Fig. KUCA A-core (Reference core)Fig. Image of KUCA A-core and fuel assembly loaded
53.8cm
39.5cm
59.1cm
0.63cm(1/4")Polyethylene
0.3086cm(1/8")Polyethylene
0.15874cm(1/16")Enriched Uranium
152.4cm
Fuel Cell×36
Polyethylene
Fuelassembly
Aluminumsheath
Collimatorregion
Polyethylene
- KUCA A-core -A solid-moderated and reflected core
F F F F F
F F F F F
F F F F F
F F F F F
12
C3 S5
S4 C1
C2 S6
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Static Experiments
Reaction rates distribution (Foil activation method)Measure 115In (n, γ) 116mIn (Exp. error: 5%)Examine effects on subcriticality, configurationOptimize collimator and beam duct
0 10 20 30 40 500
0.05
0.10
0.15
Distance from target [cm]
Nor
mal
ized
reac
tion
rate
[Arb
. uni
ts] Collimator
region Fuelregion
SVregion
Subcriticality (%Δk/k)
0.68
0.70
0.90
1.34
1.76
Fig. Measured Indium reaction rates distribution.
Fig. KUCA A-core with collimatorand beam duct.
F F F F F
F F F F F
F F SV F F
F F SV F F
22 SV 22
s'
s s s
s s s
b bs bs bs b
b bs bs bs b
f fs fs fs f
C3 S5
S4 C1
C2 S6
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
MCNP Analyses for Static Experiments
MCNP eigenvalue and point source calculationsGood evaluation by MCNP within experimental error
Experiment(%Δk/k)
MCNP (JENDL-3.3)
(%Δk/k)
MCNP (ENDF/B-VI.2)
(%Δk/k)
-0.68±0.04 -0.68 (1.4%) -0.67 (1.8%)
-0.89±0.05 -0.98 (5.7%) -0.91 (3.5%)
-1.34±0.07 -1.35 (0.3%) -1.40 (3.9%)
-1.76±0.09 -1.71 (2.9%) -1.72 (2.4%)
Table Comparison of measured subcriticality with calculated one.
0 10 20 30 40 500
0.02
0.04
0.06
0.08
0.10
Distance from target [cm]
Rea
ctio
n ra
te [A
rb. u
nits
]
Collimator region
SV region
Fuelregion
Experiment
MCNP (JENDL-3.3)
Fig. Comparison of measured In reaction rates distribution with calculated one.
( ): Relative difference, Cal. error: 0.03%Δk/k
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Optical Fiber Detection System
0 5 10 15 20 250
0.2
0.4
0.6
0.8
1.0
1.2
Subcriticality ρ [%Δk/k]
0.411.102.274.03
Distance from the center of core [cm]
6 Li re
actio
n ra
te [A
rbtra
ry u
nits
] Coreregion
Reflectorregion
0 1.00 2.00 3.00 4.00 5.000
100.00
200.00
300.00
Subcriticality | ρ| (%Δk/k)
Neu
tron
mul
tiplic
atio
n M
Meff = 1 / ( 1 - keff )
Mexp-abs (Absolute value)
Mexp-rel (Relative value)
Mcal-abs (Absolute value)
Mcal-rel (Relative value)
Fig. Li reaction rates by optical fiber detectionsystem, along to subcriticality.
Fig. Neutron multiplication by Area ratio methodapplied to Li reaction rates.
Optical fiber detection system・ LiF (ZnS): 6Li (n, α) reaction
for thermal neutrons ・ ThO2 (ZnS): 232Th fission reaction
for fast neutrons
Area ratiomethod
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Dynamic Experiments (Optical fiber system)
Pulsed neutron method (PNM)Good evaluation of subcriticality at both core and reflector positionsExamine methodology and position dependency
Fig. Measured neutron decay behavior by opticalfiber detector system.
F F F F F
1/2φ F F F F F
F F F F F
F F F F F
FC2 S6
S4 C1
C3 S5
Core
Reflector
0 0.002 0.004 0.006 0.008 0.0110-3
10-2
10-1
100
Time [Sec.]
Rel
ativ
e Li
reac
tion
rate
[Arb
. uni
ts]
- Core - Experiment MCNP
- Reflector - Experiment MCNP
ThO2 fiber
LiF fiber
HPPA5, SCK・CEN, 6-9 May 2007
C. H. Pyeon, KURRI, Japan
Subcriticality (Source Multiplication Method)
Ref. Exp. value
(%Δk/k)
MCNP(%Δk/k)
Higher-mode SM method(%Δk/k)
-0.72±0.06 -0.69 (4.2%) -0.67 (6.9%)
-2.72±0.22 -2.88 (5.9%) -2.52 (7.4%)
-5.96±0.45 -6.44 (7.5%) -5.19 (12.9%)
-8.66±0.69 -10.46 (20.8%) -7.09 (18.1%)
Table Comparison of measured subcriticality with calculated ones (with JENDL-3.3).
( ): Relative difference, Cal. error: 0.03%Δk/k
F F F F F
F F F F F
F F SV F F
F F SV F F
22 SV 22
s'
s s s
s s s
b bs bs bs b
b bs bs bs b
f fs fs fs f
C3 S5
S4 C1
C2 S6
BF
BF
BF
BF 252Cf
BF3 detectors
Subcriticality (Source Multiplication method)Measurement techniqueDetector position dependencyImprovement of precision and methodology