An Advanced Uranium Hydride Fuel Assembly Design for High...
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Department of Nuclear Science and Engineering Massachusetts Institute of Technology An Advanced Uranium Hydride Fuel Assembly Design for High Power Density BWRs Tyler Ellis ANS Student Conference Corvallis, OR March 30, 2007
Transcript of An Advanced Uranium Hydride Fuel Assembly Design for High...
Department of Nuclear Science and EngineeringMassachusetts Institute of Technology
An Advanced Uranium HydrideFuel Assembly Design for High
Power Density BWRs
Tyler Ellis
ANS Student ConferenceCorvallis, OR
March 30, 2007
Tyler Ellis 3/30/2007Slide 2Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Present State of Affairs
• 104 Operating Nuclear Power Plants in US Today• Provides for ~20% of US Electricity Generation
From http://www.industcards.com/nuclear-us-ne.htm
Indian Point 2&3
69 PWRs
Hope Creek/Salem
35 BWRs
Tyler Ellis 3/30/2007Slide 3Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Existing Plant License Renewals
Unannounced Intend to Renew Under Review Granted
Operating License Renewal
22
25
8
48
Tyler Ellis 3/30/2007Slide 4Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
How Can We Improve Performance?
• MoreIntelligentOutageManagement?
Tyler Ellis 3/30/2007Slide 5Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
How Can We Improve Performance?
• MoreIntelligentOperationalMarginUtilization?
Tyler Ellis 3/30/2007Slide 6Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
How Can We Improve Performance?
• Development of Improved Plant Components– Larger Diameter Reactor Vessel $$$$$– High Power Density Fuel Designs $
Tyler Ellis 3/30/2007Slide 7Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Hydride Fuel Design Concept
Given that MCHFR/MCPR requirements aremet, the necessary moderation is satisfiedwith a smaller amount of water
More SpaceAvailable forFuel
HigherPowerDensity
Tyler Ellis 3/30/2007Slide 8Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Fuel Design Constraints
• Geometric Constraints– same assembly unit cell size for retrofitability
• Neutronic Constraints– 5% leakage– 5 wt% enrichment– 12 month, 4 batch cycle– 5mm inter-assembly gap– negative reactivity coefficients throughout cycle
However two of these were lifted
Tyler Ellis 3/30/2007Slide 9Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Computational Tools
• MCODE Version 1.0– Stochastic– ~2 days of running time per simulation
• CASMO-4– Deterministic– ~2 minutes of running time per simulation
Tyler Ellis 3/30/2007Slide 10Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Benchmark Calculations
Eigenvalue Determination by MCODE/CASMO for a 10x10 BWR Hydride Fuel Pin
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
0 10 20 30 40 50 60 70 80 90
BU (MWd/kg)
Ke
ff MCODE
CASMO
Tyler Ellis 3/30/2007Slide 11Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Hydride Assembly Powermap
P. Ferroni “Steady State Thermal Hydraulic Analysis of Hydride Fueled BWRs.”
Tyler Ellis 3/30/2007Slide 12Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Initial Enrichment Study
Fuel Cycle Length Versus P/D for Varied Enrichments of 10x10 Hydride Fuel
5% Leakage
0
500
1000
1500
2000
2500
1.00 1.10 1.20 1.30 1.40 1.50 1.60 1.70
P/D
Fu
el C
ycle
Len
gth
(d
ays)
5%
6%
7%
8%
1740
Tyler Ellis 3/30/2007Slide 13Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Continued Enrichment Study
Fuel Cycle Length Versus P/D for Varied Enrichments of 10x10 Hydride Fuel
5% Leakage
0
500
1000
1500
2000
2500
3000
3500
4000
1.00 1.10 1.20 1.30 1.40 1.50 1.60 1.70
P/D
Fu
el C
ycle
Len
gth
(d
ays)
5%
6%
7%
8%
9%
10%
11%
12%
13%
14%
1740
Tyler Ellis 3/30/2007Slide 14Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Single Assembly VC CalculationVoid Coefficient Versus Burnup
-0.001
-0.0005
0
0.0005
0.001
0.0015
0.002
0.0025
0.003
0.0035
0.004
0 20 40 60 80 100
Burnup (MWd/kg)
VC
((D
elt
a K
)/K
)/(%
vo
id)
Reference
Hydride
Tyler Ellis 3/30/2007Slide 15Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
2x2 Colorset SimulationColorset Void Coefficient for 10x10 Hydride Fuel Over One Batch
-0.0014
-0.0012
-0.001
-0.0008
-0.0006
-0.0004
-0.0002
0
-0.2 0 0.2 0.4 0.6 0.8 1 1.2
1 Batch Lifetime
De
lta
K/K
/(%
vo
id)
GE Reference
10x10 8% Enriched
10x10 9% Enriched
10x10 10% Enriched
Tyler Ellis 3/30/2007Slide 16Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Updated Powermap
P. Ferroni “Steady State Thermal Hydraulic Analysis of Hydride Fueled BWRs.”
8%9%
Tyler Ellis 3/30/2007Slide 17Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Alternate Hydride Geometries
Table 5. 1: Overall Maximum Achievable Power for Hydride NewCore Cases Accounting for Preliminary Neutronic Results
Case Vessel
Size _p limit
(psia)
Neutronic
feasibility
region
D (mm) P/D
Fuel
Lattice
Matrix
coreQ�
(MW t)
coreQ�!
%
Feasible 11.789 1.2053 1 8_8 3909 +17.6
24.5 Feasible
BU limited
8.632 1.3368 11_11 4413 +32.8
Feasible 9.684 1.2053 11_11 4149 +24.8
Hyd-
NewCore -
5
BWR/5
36 Feasible
BU
limited
8.105 1.3105 14_14 4764 +43.3
P. Ferroni “Steady State Thermal Hydraulic Analysis of Hydride Fueled BWRs.”
Tyler Ellis 3/30/2007Slide 18Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Final ComparisonColorset Void Coefficient for Various Hydride Fuel Designs Over One Batch
-0.0014
-0.0012
-0.001
-0.0008
-0.0006
-0.0004
-0.0002
0
-0.2 0 0.2 0.4 0.6 0.8 1 1.2
1 Batch Lifetime
De
lta
K/K
/(%
vo
id)
GE Reference
11x11 Geometry, 9.2% Enriched, 24.8% Uprated
11x11 Geometry, 12.3% Enriched, 32.8% Uprated
14x14 Geometry, 11.8% Enriched, 43.3% Uprated
Department of Nuclear Science and EngineeringMassachusetts Institute of Technology
Question and Answer
Tyler [email protected]
Department of Nuclear Science and EngineeringMassachusetts Institute of Technology
Additional Slides
Tyler Ellis 3/30/2007Slide 21Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
11x11 Design Parameters
Characteristic Oxide 9x9 Hydride 11x11
24.8% Up-rated
Hydride 11x11
32.8% Up-rated
Fuel Rod Diameter (cm) 1.1176 0.9684 0.8632
Fuel Rod Pitch (cm) 1.4275 1.1683 1.1683
P/D 1.2773 1.2064 1.3535
Clad Thickness (cm) 0.0711 0.0724 0.0724
Fuel Pellet Diameter (cm) 0.9550 0.7909 0.6857
Control rod guide tube
outer/inner diameter (cm) N/A 0.9684/0.8236 0.8632/0.7184
Effective # of Fuel Rods 71 113 113
Total # of Bundles 764 956 956
Active Bundle _P (MPa) 24.40 36.00 24.50
Exit Quality 23.73 23.73 23.73
Core Power (MWth) 3310 4149 4413
Tyler Ellis 3/30/2007Slide 22Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
Geometry for 11x11 Hydride
Tyler Ellis 3/30/2007Slide 23Department of Nuclear Science and Engineering
Massachusetts Institute of Technology
What Limits LWR Power Density?
• Critical Heat Flux (PWR) and Critical Power (BWR)– Increase fuel surface to volume ratio,– improve coolant mixing,– improve water properties.
• Maximum fuel temperature below melting– Currently not being challenged but margin improvements
possible.• Peak cladding temperature during LOCA
– Reduce fuel temperature via reduced linear power or changedgeometry
– Use a ceramic cladding• Moderator to fuel ratio below that at peak reactivity
– Shift the hydrogen atoms to the solid fuel• Velocity implications for pressure drop, lift off and vibrations
– May require new grid and holdup designs
From: M. Kazimi, ACE-MIT Workshop Presentation, March 22, 2006
