Introduction Preliminary comments Validation results
Validation of FISPACT-II Decay Heat Predictionsfor LWR Spent Fuel
Michael Fleming, Jean-Christophe Sublet
Culham Centre for Fusion EnergyCulham Science Centre
AbingdonOxfordshire OX14 3DB
29 April 2015
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
Contents
Introduction
Preliminary comments
Validation results
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
I Prediction of fission decay heat is essential in safety analysisof reactors and considerable e↵ort has resulted in large (butnarrow) experimental data-set for fissions (cf CCFE-R(15)25for fusion decay heat)
I Decay heat simulation provides standard for validation offission yield data, decay data and simulation codes
I No two libraries produce the same inventories – although DHcan show uncanny similarity
I Complexity of inventory from fission makes deconvolution achallenge:
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
1E-06
1E-05
1E-04
1E-03
1E-02
1E-01
1E+00
1E+01
1E+02
1E+03
1E+04
1E-01 1E+00 1E+01 1E+02 1E+03 1E+04 1E+05 1E+06
Hea
t O
utp
ut
(kW
/kg)
Time after irradiation (s)
Heat Output (kW/kg) value/t-half for nuclide
131mTe
140Ba
132Te
129Sb
132I
91mY
135Xe
97mNb 97Zr
133I97
Nb
93Y
91Sr
92Y141La
135I
88Rb
88Kr
131Te
92Sr
139Ba
84Br
87Kr
130Sb
133mTe
101Tc
142La
146Pr
134I
134Te
105Tc
147Pr
138Cs
130mSb
131Sb
133Te
104Tc
132mSb
90mRb
89Rb
141Ba
143La
101Mo
94Y
102Tc
142Ba
138Xe
139Cs
148Pr
99mNb103Tc
145Ce
95Y
132Sb
133Sb
93Sr
137Xe
147Ce
90Rb
85Se
89Kr
103Mo
136I
86Br
87Br94
Sr98Zr
146mLa86
Se 136mI
140Cs
91Rb
144La
136Te
98Nb
145La
99Nb
139Xe
90Kr
137I146
La
135Te88Br141Cs
140Xe
144Ba
96mY 95Sr
143Ba101Nb
138I
100Nb
102Zr 100Zr89
Br102Nb96
Y
97Y
91Kr
145Ba
104mNb
100mY
93Kr
100Y
94Rb
143Cs
93Rb
98Sr
141Xe
92Rb
92Kr
102mNb
101Zr
103Nb
99Y99
Zr98
Y98m
Y142
Cs95
Rb
97nY 97m
Y96
Sr
97Sr
I 235Uth pulse using JEFF-3.1.1 DD+nFY
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
1E-06
1E-05
1E-04
1E-03
1E-02
1E-01
1E+00
1E+01
1E+02
1E+03
1E+04
1E-01 1E+00 1E+01 1E+02 1E+03 1E+04 1E+05 1E+06
Hea
t O
utp
ut
(kW
/kg)
Time after irradiation (s)
Heat Output (kW/kg) Greenwood
93Rb
95Sr
143Ba144Ba
145Ba
95Y
94Y
93Sr
94Sr
91Rb
90mRb
90Rb
89Rb
138Cs
139Cs
140Cs
141Cs
146Pr
147Pr
148Pr
141Ba
142Ba
145Ce
147Ce
142La
143La
144La
145La
WPEC SG 25 P1
86Br
87Br
88Br
89Kr
90Kr
100Nb
101Nb
105Tc
104Tc
103Tc
103Mo
102Tc
99Nb
98Nb
132Sb
136I
136mI
137I
137Xe
139Xe
140Xe
WPEC SG 25 P297Sr92
Rb
96Y
102Nb
WPEC SG 25 P399Zr142
Cs
I Greenwood/WPEC25 priority nuclides shown
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Introduction Preliminary comments Validation results
Fission decay heat has been the subject of several experiments overseveral decades. Even those experiments with the same fissile areall unique, notably di↵ering in:
I Irradiation duration and flux spectrum
I Measurement techniques
I Fission rate determination
I Sample preparation/removal/post-irradiation processing
I Contamination corrections (capture/epithermal/impurity)
ICorrection methodology (finite to pulse, noble loss, etc)
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Introduction Preliminary comments Validation results
Author Method Nuclide(s) Irr. (s) Year
Yarnell, LANL Calor. 233U 235U 239Pu 2E4 1980Dickens, ORNL �,� 235U 239Pu 241Pu 1-100 1980Baumung, KfK Calor. 235U 200 1981Akiyama, YAYOI �,� 232Th 233U 235U 10-300 1982
238U 239PuJohansson, Uppsala �,� 235U 238U 239Pu 4-120 1987
Schier, Lowell �,� 235U 238U 239Pu
Introduction Preliminary comments Validation results
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1 10 100 1000 10000 100000
Dec
ay h
eat
(MeV
/fis
sion)
Time (s)
100 ms Irradiation1 s Irradiation
10 s Irradiation100 s Irradiation
1000 s IrradiationBurst Function
Dickens total
I 241Pu thermal fission
I No individual experiment covers pulse
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Introduction Preliminary comments Validation results
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0.1 1 10 100 1000 10000 100000
Tota
l dec
ay h
eat
(MeV
/fis
sion)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Tobias totalDickens total
I Capture contamination depends upon preciseknowledge of inventory and spectrum (235U shown)
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
FISPACT-II is a general-purpose simulation code, completelyrewritten from legacy FISPACT in modern Fortran
I Can use any ENDF-format nuclear data
I Calculates numerous observables: activity, heat, various doses,detailed inventory, sophisticated pathway trees
I RRR+URR self-shielding with PT from CALENDF
I Generate sources with multi-di↵erential data
I Developed to accommodate a complete, technological library(eg TENDL) with all isomeric states, HFR, double-di↵ ...
I Provides robust simulation methodology that can be appliedto reactor operation, activation/transmutation, fusionapplications, high-energy, security, astrophysics ...
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Introduction Preliminary comments Validation results
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0.1 1 10 100 1000 10000 100000
Tota
l dec
ay h
eat
(MeV
/fis
sion)
Time (s)
JEFF3.1.1GEF4.2
UKFY4.2Tobias total
Dickens total
I 235U thermal pulse total heat
I Varied nFY with JEFF-3.1.1 DD simulation
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Introduction Preliminary comments Validation results
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.1 1 10 100 1000 10000 100000
Bet
a d
ecay
hea
t (M
eV/f
issi
on
)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12Tobias betaLowell beta
Dickens beta
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.1 1 10 100 1000 10000 100000
Gam
ma
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Tobias gammaLowell gamma
Dickens gamma
I JEFF-3.1.1 nFY simulation 235U pulse beta (L) gamma (R)
I Well-known Pandemonium �-deficiency can be probedthrough multi-library comparison
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
0.35
0.4
0.45
0.5
0.55
0.6
0.65
0.7
0.75
0.8
1 10 100
Gam
ma
dec
ay h
eat
(MeV
/fis
sion)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Tobias gammaLowell gamma
Dickens gamma
I Example: isolate �-heat of 235U pulse at 10susing same nFY to compare DD
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Introduction Preliminary comments Validation results
Nuclide JEFF3.1.1 ENDFB7.1 JENDL4.0 DECAY12
Rb92 3.12 3.85 3.85 3.13Rb93 3.21 3.11 2.80 3.21Nb102 1.56 2.50 0.64 1.56Y96 0.15 0.15 2.23 0.15Kr91 1.98 1.99 2.00 1.98Y96m 1.93 1.85 1.85 1.93Ba143 2.13 2.13 1.81 1.77Nb102m 0.64 0.06 0.95 0.06
I Normalised heat output in W/fission for 235U pulse at 10s
I Some appear corrected only in JENDL/ENDF, some may bere(mis?)-allocation to isomer, such as Nb102m.
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
0.65
0.7
0.75
0.8
1 10 100
Gam
ma
dec
ay h
eat
(MeV
/fis
sion)
Time (s)
JEFF3.1.1GEF4.2
UKFY4.2Tobias gammaLowell gamma
Dickens gamma
I Same story, but now variety of nFY for�-heat of 235U pulse at 10s
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
Nuclide JEFF3.1.1 GEF4.2 UKFY4.2
Rb92 3.12 2.90 3.34Rb93 3.21 3.14 3.95Sr95 1.91 2.08 2.14Y97 1.14 1.88 1.64
Nb102 1.56 1.23 0.58Kr91 1.98 1.87 1.64Y96m 1.93 0.38 4.37Ba143 2.13 1.99 1.97
I Normalised heat output in W/fission for 235U pulse at 10s
I Uncanny di↵erences in dominant fission production yields,isomeric yields?
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Akiyama total
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Akiyama total
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
2.2
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Akiyama total
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1ENDFB7.1JENDL4.0DECAY12
Akiyama total
I Akiyama 3,5,8,9 vs 400keV (JEFF nFY)
http://www.ccfe.ac.uk
Introduction Preliminary comments Validation results
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1GEF4.2
UKFY4.2Akiyama total
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1GEF4.2
UKFY4.2Akiyama total
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
2.2
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1GEF4.2
UKFY4.2Akiyama total
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
10 100 1000 10000
To
tal
dec
ay h
eat
(MeV
/fis
sio
n)
Time (s)
JEFF3.1.1GEF4.2
UKFY4.2Akiyama total
I Akiyama 3,5,8,9 vs 400keV nFY (JEFF DD)
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Introduction Preliminary comments Validation results
Some thoughts:
I Decay heat experiments are complex, old(er than me), andcould benefit from review for specific fuels/times
I Meta-analysis of experiments with systematic challenges doesnot improve data quality
I Integration of new decay data needed for �/� heat
I Di�cult to assign superiority of files due to spread ofexperimental data
I FISPACT-II allows versatile simulation which can probe DHsubtleties and expose unresolved issues with DD and/or nFY
http://www.ccfe.ac.uk/EASY.aspx
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Introduction Preliminary comments Validation results
Thank you for your attention
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IntroductionPreliminary commentsValidation results