neutronic analysis of th-233u self - a monte carlo reactor...
TRANSCRIPT
Neutronic analysis of Th-233U self
sustainable BWR fuel cycle with BGCore
and Serpent Codes
by
Y. Shaposhnik, E. Shwageraus
Department of Nuclear Engineering,
Ben-Gurion University of the Negev
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 2
Outline
Th-233U fuel cycle
BWR Seed-Blanket assembly
Computational tools BGCore system Serpent
Results: Code-to-Code comparison Nutronic parameters (kinf, FIR, nuclide densities)
Computational efficiency (CPU time, memory)
Summary and conclusions
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 3
Introduction to Th-233U fuel cycle
Self-sustainable fuel cycle:
ThO2-233UO2 Fuel with continuous recycling of 233U
Standard ABWR balance of plant
Heterogeneous reactor assembly structure
Modifications should not compromise reactor safety
Evaluated parameters:
K-inf vs. time
Fissile Inventory Ratio -
loading mass fissile Initial
at time mass Fissile tFIR
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 4
Th-233U methodology
0
1
2
3
4
1E-03 1E-02 1E-01 1E+00 1E+01 1E+02 1E+03 1E+04 1E+05 1E+06 1E+07
Energy, eV
Fis
sio
n n
eu
tro
ns y
ield
per a
bso
rp
tio
n
U-233
U-235
Pu-239
Core
Power
Void
Coefficient
Conversion
Ratio
Conversion Ratio
hard spectrum
Hard spectrum
Void Coefficient >0
Void Coefficient >0
heterogeneous geometry
Heterogeneous geometry
limits core power density
η-factor as a function neutron energy (JEFF-3.1)
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 5
Th-233U Seed-Blanket BWR assembly
BWR SB radial configuration
9x9 lattice
No water holes
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 6
Axial configuration
3 axial Seed zones (Th-233UO2)
4 axial Blanket zones (ThO2)
Dimensions derived from prior analyses
Bottom plenum - 40 cm
Blanket 1 - 40 cm
Blanket 2 - 30 cm
Seed 2 - 20 cm
Blanket 3 - 30 cm
Seed 3 - 30 cm
Blanket 4 - 50 cm
Top plenum - 40 cm
Seed 1 - 20 cm
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 7
Axial configuration
Variable seed enrichment to manage power peaking
18 burnable zones
Bottom plenum - 40 cm
Blanket 1 - 30 cm
Blanket 2 - 30 cm
Seed 2 - 20 cm
Blanket 3 - 30 cm
Seed 3 - 30 cm
Blanket 4 - 50 cm
Top plenum - 40 cm
Seed 1 - 20 cm
233UO2 Fraction Zone size Moderator density
[w/o] [cm] [
g/cc]
Top Plenum - 40 0.14421
Blanket 4-b 0 40 0.14421
Blanket 4-a 0 10 0.14457
Seed 3-d 14 10 0.15406
Seed 3-c 13 10 0.17560
Seed 3-b 12 5 0.19586
Seed 3-a 10 5 0.21274
Blanket 3 0 30 0.22372
Seed 2-d 14 5 0.23655
Seed 2-c 15 5 0.26300
Seed 2-b 14 5 0.29318
Seed 2-a 13 5 0.33603
Blanket 2 0 30 0.36729
Seed 1-d 13 5 0.40522
Seed 1-c 13 5 0.49771
Seed 1-b 10 5 0.63108
Seed 1-a 7 5 0.74098
Blanket 1-b 0 10 0.74564
Blanket 1-a 0 30 0.74573
Bottom Plenum - 40 0.74573
Type
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 8
Description of computational tools
BGCore
Neutron transport solution by MCNP
Multi-group cross sections for depletion (SARAF)
Thermo-hydraulic feedback (THERMO)
Serpent (ver. 1.1.14)
Unique features
delta-tracking method
uniform energy grid for cross section data
depletion using CRAM-method
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 9
Results: Nutronic parameters
Neutron multiplication factor - kinf
* PCC – Predictor Corrector algorithm in Serpent
0.990
0.995
1.000
1.005
1.010
1.015
1.020
1.025
1.030
1.035
1.040
1.045
1.050
1.055
1.060
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
kin
f
kinf - Serpent with PCC
kinf- BGCore
kinf - Serpent no PCC
Δkinf=364 pcm Δkinf ~ 360 pcm
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 10
Results: Nutronic parameters
Fissile Inventory Ration - FIR
* PCC – Predictor Corrector isotope estimation in Serpent
0.975
0.980
0.985
0.990
0.995
1.000
1.005
1.010
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
FIR
FIR - Serpent with PCC
FIR - BGCore
FIR - Serpent no PCC
ΔFIR ~ 0.4 %
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 11
Results: Nutronic parameters
Mass of 235U
Mass of 233Pa
Mass of 233U
Under investigation
235U
233U
233Pa
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
Mass o
f 2
35U
[kg
]
U235-Serpent with PCC
U235-BGCore
U235-Serpent no PCC
6.05
6.10
6.15
6.20
6.25
6.30
6.35
6.40
6.45
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
Mass o
f 2
33U
[kg
]
U233-Serpent with PCC
U233-BGCore
U233-Serpent no PCC
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
Mass o
f 2
33P
a [
kg
]
Pa233-Serpent with PCC
Pa233-BGCore
Pa233-Serpent no PCC
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 12
Remarks on computational efficiency
Total Execution time
Machine Configuration
SUN Intel(R) Xeon X2270
16 CPU’s 2933 MHz
24 GB RAM memory
Speed-Up
factor
3CPU - Serpent no PCC
Exe. Time [min]
3CPU - Serpent with PCC
Exe. Time [min]
1.59 1113.92 1771.19
Speed-Up
factor
3CPU - Serpent no PCC
Exe. Time [min]
3CPU - BGCore no PCC
Exe. Time [min]
5.77 1113.92 6431.80
Speed-Up
factor
3CPU - Serpent no PCC
Exe. Time [min]
16CPU - BGCore no PCC
Exe. Time [min]
2.25 1113.92 2508.60
* PCC – Predictor Corrector algorithm in Serpent
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 13
Memory Limitation
Machine Configuring
SUN AMD Opteron 2218
4 CPU’s 2613 MHz
32 GB RAM memory
Machine Configuration
SUN Intel(R) Xeon X2270
16 CPU’s 2933 MHz
24 GB RAM memory
Serpent Execution with 4 CPU
Memory Swapped
Start Serpent Start Serpent
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 14
CPU time
Depletion + Transport Execution time
0
20
40
60
80
100
120
140
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
Dep
leti
on
+N
eu
tro
nic
Execu
tio
n t
ime [
min
]
Exe.time - BGCore 3 CPU
Exe.time - BGCore 16 CPU
Exe.time - Serpent 3 CPU With PCC
Exe.time - Serpent 3 CPU No PCC
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 15
CPU time
Total Execution time
Machine Configuring
SUN AMD Opteron 2218
4 CPU’s 2613 MHz
32 GB RAM memory
Speed-Up
factor
1CPU - Serpent
Exe. Time [min]
1CPU - BGCore
Exe. Time [min]
7.59 3812.40 28940.30
Speed-Up
factor
1CPU - Serpent
Exe. Time [min]
4CPU - Serpent
Exe. Time [min]
3.76 3812.40 1013.93
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 16
Summary and Conclusions
Good agreement in neutronic parameters between Serpent and BGcore Up to 360 pcm in multiplication factor (at EOL)
Up to 0.4% in Fissile Inventory Ratio (at EOL)
Minor discrepancy in 233U concentration (under investigation)
Calculation performance Serpent is ~ 7 faster than BGCore
1CPU – 7.6
3CPU – 5.8
Memory allocation restricts Serpent performance
Bottleneck - Initial data preparation
At least 1 additional CPU is lost
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 17
Thank you
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 18
Statistical Accuracy - k-eigenvalue
100,000 - Source neutrons
50 - Inactive cycles
100 - Active cycles
1.0 - Initial guess for k-eigenvalue
set pop 100000 100 50 1.0 - Serpent
kcode 100000 1.0 50 150 - MCNP
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
1.05
1.10
0 50 100 150 200 250 300 350 400 450 500 550
Cycle
kin
f
0.88
0.89
0.9
0.91
0.92
0.93
0.94
0.95
0.96
0.97
0.98
0.99
Sh
an
no
n E
ntr
op
y
k
Shannon
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 19
Problem definition
Data libraries
Operational
parameters
Materials
Geometry
MCNP
3D core neutronics
SARAF
Fuel depletion
(composition)
THERMO
Temp. distribution
Output
Keff, Fuel Composition
Spent Fuel Emissions
Power Distribution
Moderator/Coolant, Fuel
and cladding Temperatures.
Initial TH conditions
BGCore system Serpent
Problem definition
Data libraries
Operational
parameters
Materials
Geometry
PSG
3D core neutronics
BURNUP
Fuel depletion
(composition)
Output
Keff, Fuel Composition
Power Distribution
2011 Serpent International Users Group Meeting - Helmholtz-Zentrum Dresden-Rossendorf (HZDR) September 15-16, 2011 20
0
1000
2000
3000
4000
5000
6000
7000
0 500 1000 1500 2000 2500 3000 3500
Time [EFPD]
To
tal Execu
tio
n t
ime [
min
]
Exe.time - Serpent 3CPU
Exe.time - BGCore 3CPU
Exe.time - Serpent No PCC 3CPU
Exe.time - BGCore 16 CPU