gamma scan validation of simulate5 bwr model features
TRANSCRIPT
Rank the
picture below
the Core
template slideSlide title
36pt
Slide subtitle
18pt
Gamma Scan Validation of SIMULATE5 BWR Model Features
2009 European Users Group Meeting
Chester, UK September 16-18 2009
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Overview
• SIMULATE5 Models Specific to BWR
– LPRM Tube Modeling
– Intra-nodal Void Quarter-Bundle Thermal Hydraulic (QTH) Model
• LPRM Tube Model Description
• Intra-nodal Void Model
• Background on Hatch Gamma Scan
• Validation of LPRM Tube Model via Hatch Gamma Scan Results
• Validation of Intra-nodal Void Model via Hatch Gamma Scan Results
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
LPRM Tube ModelingLPRM
Simplified LPRM
Pin Powers (No LPRM) Pin Powers (LPRM) Difference *100
1.12 1.13 1.0
0.97 1.11 0.98 1.12 0.8 0.9
1.09 0.97 1.08 1.09 0.98 1.09 0.9 0.7 0.6
1.02 1.16 0.97 0.89 1.02 1.16 0.98 0.90 0.8 0.7 0.5 0.2
0.99 1.10 0.90 0.86 0.89 1.00 1.11 0.90 0.86 0.88 0.6 0.6 0.3 0.0 -0.3
1.14 1.12 0.40 0.88 0.95 1.05 1.14 1.13 0.40 0.88 0.95 1.03 0.6 0.5 0.2 -0.2 -0.9 -2.0
1.13 1.01 1.11 1.07 1.12 0.94 1.08 1.13 1.01 1.11 1.07 1.11 0.91 1.02 0.6 0.4 0.2 -0.4 -1.5 -2.7 -6.0
LPRM Tube, which has significant impact on N-N corner pin,
is modeled explicitly in SIMULATE-5
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Improvements:BWR Quadrant-Assembly TH (QTH)
• Performed after conventional TH calc.
• Input:
- Total assy inlet flow rate
- Quadrant-power from radial submesh calc.
• Output:
- Quadrant-assy flow, void, ...
- Density feedback to radial submesh XS
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Improvements:BWR Quadrant-Assembly TH (cont.)
3 options:
1. Non-communicating Q-channels (eg. SVEA)
- Flow from total axial pressure drop equalisation
2. Cross Flow I
- Lateral momentum equation
- Turbulent mixing and void drift neglected
3. Cross Flow II
- Continuous pressure equalisation in z-direction
- Fast convergence
pax
plat
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Improvements:BWR Quadrant-Assembly TH (cont.)
Void and power in 4 BWR Sub-Channels
0
50
100
150
200
0 5 10 15 20 25
z
NW
SE
NW
SE
0
20
40
60
80
0 5 10 15 20 25
z
SE
NW
POWER VOID
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Improvements:BWR Quadrant-Assembly TH (cont.)
Skewed void impacy on pin powers
Difference (Skewed void) – (Flat void) (%)
-8
-4
0
4
8
12
0 5 10 15 20 25
Max pin
Pin (1,1) - CR
Pin(8,8) - Det
Avg pin
z
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Hatch 1 Gamma Scan Background
• Extensive Gamma Scan Measurements following Cycles 1 & 3
• 106 Bundles were Scanned Following Cycle 1 (EPRI NP-511, August 1978)
– 35 Controlled bundles
– 71 Uncontrolled bundles
– 4 Bundles were disassembled for Rod Scanning (40 out of 49 rods)
– 1 Deep controlled (notch 14) Bundle HX0373
– 1 Shallow controlled (notch 34) Bundle HX0393
• 126 Bundles were Scanned Following Cycle 3 (EPRI NP-2105, August 1978)
– 14 Controlled bundles
– 112 Uncontrolled bundles
– 3 Bundles (7x7) were disassembled for Rod Scanning (40 out of 49 rods)
– 1 Bundle (8x8) were disassembled for Rod Scanning (54 out of 62 rods)
– 1 Shallow controlled (notch 34) Bundle HX0260
• Analysis of the Rod Scanned Bundles was the Primary Focus of the
benchmarking
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Hatch 1 Cycle 1
Gamma Scan Bundle LocationsHX0373
HX0393
HX0169
HX0141
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Hatch 1 Cycle 3
Gamma Scan Bundle location
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Gamma Scanning Calc. in SIMULATE-5
• Gamma scanning analysis built into SIMULATE-5
Ba140 is tracked explicitly per pin (as well as per node)
is solved to give
• The half life of Ba140,Ba140, is 12.8 days, the tracking starts at least 2000 hours before
the gamma scanning takes place. The initial condition is that the Ba140 concentration is
in equilibrium.
• The fission yield for Ba140, iBa140, per pin is calculated from CASMO-5 and tabulated in
CMS-Link library.
iBa
G
g
gigif
Ba
i
i Ndt
dN140
1
,
140
140 140
140
,
1140
( ) (0) 1Ba Ba
Ba Gt ti
i i f gi gi
gBa
N t N e e
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of LPRM Tube Modeling (Uncontrolled HX0038, Cycle 3)
SIMULATE5 With QTH & Without LPRM Tube Modeled
SIMULATE5 With QTH & LPRM Tube Modeled
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of LPRM Tube on NNC Rod Power
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of LPRM Tube Model on WWC & NNC Rods
in HX0373 Cycle1
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of LPRM Tube on NNC Adjacent Rods (Average Power)
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of QTH Model
(Deep Controlled Bundle HX0373, Cycle 1)
SIMULATE5 With QTH & LPRM Tube Modeled
SIMULATE5 Without QTH & LPRM Tube Modeled
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of QTH Model on WWC Rod Relative Power
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
TIP Comparison Near Bundle HX0373
Calculated result overpredicts
by >10% at peak
Dominated by NNC pins
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of QTH Model on WWC Rod(Deep Controlled Bundle HX0373, Cycle 1)
Underprediction of ~25% at
peak at WWC (NO QTH)
QTH improves by ~9% at peak
at WWC
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of QTH Model on WWC Rod(Deep Controlled Bundle HX0373, Cycle 1)
Pin normalized results
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of QTH Model on NNC Rod(Deep Controlled Bundle HX0373, Cycle 1)
Behavior for NNC consistent
with TIP error of ~10%
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Effect of QTH Model on WWC & NNC Rods in
HX0373 Cycle1
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester
Summary
• SIMULATE-5 accurately predicts the pin Ba-140 number densities
(and therefore pin powers)
• The LPRM tube impacts the corner and surrounding pins in the NNC.
This appears as a systematic bias (overprediction) of pin powers
(~5% in the corner). SIMULATE-5 explicitly models the LPRM tube
as a branch case in the cross section library and pin reconstruction.
• Quarter-assembly T-Q (QTH or skewed void) model impacts cases
of deep control rod insertions, where extreme power and void
gradients (>40%) are observed. Improvements of ~9% are observed
in WWC pins for an assembly with deeply inserted control rod
although peaking results were still underpredicted.
• Further refinements of sub-channel T/H model continues with focus
on consistency between neutronic and T/H submesh.
Slide title
pt
Text
24 pt
Bullets level 2
20 pt
2009 User‘s Group Meeting September 2009, Chester