galileo fuel rod performance code and methodology for bwrs ... · " galileo was calibrated to...

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GALILEO Fuel Rod PerformanceCode and Methodology forBWRs and PWRs

loan ArimescuPhilippe BellangerChristophe Garnier

Jerry HolmHorst LandskronPierre Mailhe A

AREVA

Agenda

lo Objectives

Oo Introduction

Po GALILEO - Selected Topics* Thermal Conductivity Degradation (TCD) with Burnup* Fission Gas Release (FGR)* Gaseous Swelling and Advanced Mechanical Models* Crud, Corrosion and Hydrogen Pickup

0- GALILEO MOX* Fuel Modeling* Non-Proliferation (NP) vs. Reactor Grade (RG)* Applicability to Dry Conversion Process" Impact on Margin

Oo Summary0. Next steps

A2014 June 2 4 th - GALILEO post-submittal meeting 2 AR EVA

M M 11 M 60 W -= M -M - -M nMM

so M - m - m, - M so some=

Meeting Objectives W

lo-Present a summary of the GALILEO topicalreport

OoPresent in depth a sub-set of key topicsK Models applicable to both U0 2 (with and without

gadolinium) and MOX

* MOX key models and considerations

OoDiscuss the NRC review and approvalprocess for the GALILEO topical report

K Goal is an SER by December 31, 2015

A2014 June 24th - GALILEO post-submittal meeting 3 AR EVA

GALILEO Topical ReportObjectives

Oo Produce state-of-the-art design code and methodsto license AREVA fuel

* Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR)* All AREVA cladding and fuel types4 Address all observed phenomena, including fuel thermal

conductivity reduction with burnup* Code backed by extensive calibration and validation database* Statistical methodology

lo Replace legacy codes RODEX2/2A, TACO3,GDTACO

* Incorporate modern fuel thermal conductivity models* Add hydrogen models to address future NRC changes to loss of

coolant accident (LOCA) and control rod ejection criteria

Oo Provide a means to transition to a single fuelperformance code


-NMO-M eU OW " Mm M mo M -

M" Ps am - m - l no - 1 MW 0 -m -o I s ofam up

Requirements and Capabilities

Po Criteria to be evaluated (NUREG-0800, Section 4.2)K Fuel temperature for anticipated operational occurrences

(AOOs)K Cladding transient strain (AOOs)K Rod internal pressureK Cladding corrosionK> Cladding hydrogen uptaket> Cladding collapset> Cladding fatigue

Po LOCA criteriaK GALILEO will be used to generate LOCA initialization dataK Implementation in LOCA methodology will be addressed in

separate topical reports A2014 June 2 4 th - GALILEO post-submittal meeting 5 AR EVA

Proprietary Meeting

This concludes the public portion of AREVA's presentation.


-f OW 66 -0 =- 000 Am w **- w I" to M - - -- i-i

-M A WE Wk W M) W M. -M 1M

Requirements and CapabilitiesAOO Criteria

OP Fuel temperature

K Calculated maximum fuel temperature shall remain lessthan the fuel melt temperature

K Lower bound melting temperature includes effect ofgadolinia, Pu content of MOX, and is a function of exposure

Oo Cladding transient strain

* Transient-induced tangential outside diameter (OD) strain,elastic + plastic, excluding irradiation growth and steady-state creep down, shall not exceed 1%

* Hydrogen limits established to preserve adequate ductilityat higher exposures

A2014 June 2 4 th - GALILEO post-submittal meeting 7 AREVA

Requirements and CapabilitiesNormal Operation Criteria

N Rod internal pressure* Rod internal pressure limited to prevent unstable increase in the pellet-clad gap, i.e.,

the outward cladding creep shall not exceed fuel swelling rate* To avoid hydride reorientation, rod pressure is restricted to:

*<C

Oo Cladding oxidation, hydriding, and crud buildup+ Calculated oxidation shall be less than:

-[

+ Hydrogen shall be less than:o[

+ The thermal effect of crud is taken into account


A= am M wea N is11. M is U M I

- - , m Iwe mtw W mM o N O


01 Cladding cyclic fatigue0 Cladding fatigue usage factor shall not exceed 1.0. The fatigue design

curve (O'Donnell & Langer) includes a factor of safety of either 2 onstress, or a factor of 20 on the number of cycles, whichever is moreconservative

0. Cladding creep collapse

K Axial gap formation [] to provide adequate support to the cladding (RODEX4

methodology)

*If greater than[ ]toshow the following sub-criteria are satisfied (CROV methodology):



Oo Hydrogen uptake criterion for Zry-2 cladding

* Hydrogen uptake model developed for RODEX4

* RAI response with model submitted in November 2013

* The GALILEO topical report refers to the separate submittal

* AREVA plans to update GALILEO topical report to includethis model following NRC approval for use in RODEX4

* This allows for a single model9 Review of implementation in GALILEO will be required


s 0 o m -M " M W M No m - mM M, 4" ,

N" mM m M m" M " M M am W =- -

Requirements and CapabilitiesStatistical Methodology

lo Follows the same statistical methodology described inBAW-10247PA for RODEX4

" GALILEO was calibrated to provide a best-estimate response with aminimum of bias and no significant local bias over the range ofapplicability

" Fuel rods (power histories) and uncertainties are sampled andpropagated through the code using known statistical variances of theinput variables


Requirements and CapabilitiesReactor Operations Scenarios

lo Normal Operation

* Analysis is made separately for each reload (batch) of fuelin the core

e Power histories for the reload are calculated using current neutronic coresimulator codes for BWRs and PWRs

* BWR and PWR normal operations scenarios are evaluatedin a very similar manner

2A2014 June 24th - GALILEO post-submittal meeting 12 AR EVA

m m m w m= M o•-m M m "=I" m M ýý M M

mm urn mm - mm - mm - -


lo-AOOs

) Effort was made to consolidate BWR and PWR methods tothe extent feasible - some differences continue to exist

" BWRs and PWRs use different methods for power monitoring, and the fuelrod power limits are not defined in the same way

" Historical differences exist in the treatment of strain between BWRs andPWRs

K The BWR AOO method with GALILEO was derived from theRODEX4 methodology

* The same types of transients are evaluated, and GALILEO was substitutedfor RODEX4

0 The PWR AOO method is based on the COPERNICmethodology

* The PWR AOO methodology accounts for uncertainties, as with theRODEX4 methodology



Po Evaluation of AOOs+ For BWRs, slow transients are embedded in the steady-state

power histories for the evaluation of the transient strain criteria(cladding strain and fuel melt). Additionally, the transients areincluded to account for their effect on rod internal pressure.

+ For PWRs, transient power spikes are included in the steady-state power histories only for their effect on rod pressure. Thetransient strain criteria for PWRs are evaluated separately fromthe power history analysis.

+ Compared to the COPERNIC methodology, uncertainties aretaken into account in the analysis of AQOs for PWRs, as well asof BWRs.


=M " =a NO M M M M

m m I"- m M Mmm- M M lm m m


Po Evaluation of AOOs (continued)<>A separate analysis is performed using GALILEO on the hot

node to determine an allowable overpower factor based on themaximum allowed cladding strain and fuel temperature. Thismethod is used for BWR slow transients and PWR transients.

" The overpower factor result is used in conjunction with an approvedPWR systems transient code to evaluate setpoint limits to protect thetransient criteria.

* The overpower factor result is used for BWRs to establish flow-dependent LHGR multipliers that protect the transient criteria for slowtransients.

0 For BWR fast transients, the power excursions calculated froman approved reactor system transient code (e.g., COTRANSA2)are evaluated by GALILEO for cladding strain and fueltemperature. Linear heat generation rate (LHGR) multipliers areestablished as a function of power to protect the transientcriteria.

15 AREVA2014 June 24th - GALILEO post-submittal meeting

Requirements and CapabilitiesGALILEO Fuel Rod Code

IUTF

Rod Characteristics

Pellet & Cladding Geometry

Material

PUT DATAIrradiation Conditions

Thermal.Hydraulic Conditions

Power Histories

Pellet and CladdingThermilcs

Cla Corrosion

BAI aLEO Lt and Cladding FRlselonsG

Mechanics Helium Bala

U ~1

1711FFPelle

OUTPUT RESULTS

Fuel and Clad Temperatures

Fuel and Clad Stresses and Strains

Outer Zirconia Thickness and Hydrogen Content

Fission Gas Release and Helium Balance

Rod Internal Pressure- A16AREVA2014 June 2 4 th - GALILEO post-submittal meeting

M M M " M M " M M M M = 3-0 M 111111110 M M

M M M M M mM M W - M IM M -- an

Requirements and CapabilitiesGALILEO Highlights

Po A single code for both BWR and PWR

< Cladding models include Zry-4, M5®, and Zry-2, stress-relief (SR) annealedand recrystallized (RX) annealed

Po Some models adapted from RODEX4, COPERNIC and CARO-E3,as part of a best practice effort

Oo New models and model improvements based on research anddevelopment programs

GALILEO incorporates modern technology and best practices.



Model Comes from: New features___________ ~~~~~RODEX4 COP2 CARO-E _______________________

Fuel Pellet Radial Power Profile Y Use of the sophisticated pin cell code CIRTHE and interpolationFtechniques

Coolant model Y Y Y IAPWS-IF97 tables for water and steam

New contact conductance modelPellet-cladding gap conductance YInterac soothng model

Interface smoothing model

THERMAL (Lucuta's Kinetic radiation damageFuel Thermal conductivity radiationFuel T c idamagie) Improved conductivity modeling at high temperature (Fink correlation)

Rim model Partly Temperature thresholdImpact on density and pellet strain

Pellet relocation Partly

High burnup release enhancement model considering Xe concentrationFission Gas Release Partly Partly limit and bubble interlinkage

Grain growth

GAS Helium models He producion and release modeling for MOX fuel (from CEA)

Contribution of a fraction of the gaseous porosity to the open porosityRod free volume and inner pressure (open porosity) Y Lwrpeu eprtr orltoLower plenum temperature correlation


M M " M = -0 M M M m M m -- 7

m -mm MM-m .... m = m• m m - m


-- - - I - I

Model Comes from:Comes from: New features

RODEX4 COP2 CARO-EDensification Y

Solid-Swelling YGaseous Swelling Partly _AREVA model

PELLETSTRAIN Fuel creep CEA modelSTRAINS

Pellet Relocation YPellet cracking YGLOVD New AREVA modelZr4 low stress creep YZr4 high stress creep YZr4 plastic strain Y

Zr4 free growth Partly New AREVA model after contact

CLAD STRAINS M5 low stress creep Partly Creep anisotropy modelingM5 high stress creep Y

M5 plastic strain Y

M5 free growth New AREVA modelSR and RX Zr2 creep Partly Creep anisotropy modelingSR and RX Zr2 free growth PartlyHourglassing model Partly Improved RODEX4 modelClad shell model new AREVA model

MULTI- Cladding ridging Partly Improved RODEX4 modelDIMENSIONAL _________

MODELS Cladding ovality YCROVINC (CROV)Dish filling Partly Improved RODEX4 model

Zr4 corrosion YZr4 H2 pick-up model Y

CORROSION M5 corrosion YM5 H2 pick-up model _New AREVA model

Zr2 corrosion Y A2014 June 24th - GALILEO post-submittal meeting 19

AW-1k

AREVA

Database Highlights *lo Database is composed of 1439 fuel rods selected from

over 2000 rods covering high burnups (>75 GWD/MTU)and high duty plants (>35 kW/m)

lo PWR vs. BWR

lo Rod Type Breakdown

Po Test reactor vs. commercial reactor data

>> Extensive and balanced validation database2014 June 2 4th - GALILEO post-submittal meeting

A2o AR EVA

MW-rM- M M =-10 - om we - mso M M M 2-ý

M arm M wk M m w M -4www MMwM MM

Ranges of Applicability

Fuel types U0 2, U0 2-Gd 2O3 and MOX (NP andRG)

Cladding types Zircaloy-4, M5®, Zircaloy-2 (SR andRX)

Fuel rod burnup (all fuel types) Up to 62 GWd/tM for full-length rodand equivalent for part-length rods

A21 AREVA2014 June 24th - GALILEO post-submittal meeting 2 R V

GALILEO - Selected Topics

OoThermal Conductivity Degradation

lo Fission Gas Release

OoAdvanced Pellet Mechanical Models

0o Corrosion and Hydrogen Pickup

2 A22 AR EVA2014 June 2 4 th - GALILEO post-submittal meeting

No- - wMýW " -- M -="lf

M lo M M M = am M-o"= w a

Fuel TCDGeneral Background, Phenomenology

A24th - GALILEO post-submittal meeting 23 AR EVA2014 June;

Fuel TCDU0 2 Model Formulation

Oo Fully dense U0 2 fuel TCD model formulation:

2 A24 AR EVA2014 June 24th - GALILEO post-submittal meeting

No= MM M M am M M mu m m M nom M M M " mS

M- -M -M- ~r

Fuel TCDCalibration Methodology

A25 AR EVA2014 June 24th - GALILEO post-submittal meeting

Fuel TCD IBurnup, Temperature Trends

lo Fully dense (100% TD) U0 2 fuel thermal conductivity modeltrends vs. burnup and temperature:


M m M a•m - mM o M M M M mm

w " M M MN - -w M " M

Fuel TCDCalibration, Validation Results

lo No bias vs. burnup on the calculated fuel temperature upto very high burnup (102 GWd/tM) A

2014 June 24th - GALILEO post-submittal meeting 27 AR EVA

Fuel TCD

0o Satisfactory UO2 fuel temperature predictions up to veryhigh burnup (102 GWd/tM) ^

2014 June 24th - GALILEO post-submittal meeting 28 AREVA

mM MWMntom m M " m Moni0

Ma mMn- a aMa M a - a - a - a aI

Fuel TCD

Po Satisfactory U0 2 fuel temperature predictions at high burnup

(62 GWd/tM) for LHGR ranging from 11 to 31 kWIm A2014 June 24th - GALILEO post-submittal meeting 29 AR EVA

Fuel TCDI[

No Satisfactory U0 2 fuel temperature predictions at highburnup (60 GWd/tM) up to fuel melting


M m-mm m M m - m m - m - am

= - = U = M M I M M M M w m - M M M

Fuel TCDMixed Fuels (MOX, Gd)U

P Satisfactory fuel temperature predictions vs. burnup formixed fuels (MOX, Gd) A


Fission Gas Release *Po Short overview about the model and the main release

mechanisms

Po Results* Enhanced release

" Validation


M M M M -M M M -M M-

= M = M m m -= = = = = = - - = m M

FGRMechanisms: Athermal Release

lo Recoil and knockout of fission gas (FG) atomsthrough free surfaces (cracks, open pores)

lo Temperature independent

Oo Increases with burnup and open porosity

lo Remains low with acceleration at high burnupassociated with the formation of fuel pellet rim.


FGRMechanisms: Thermal Release (I)


M M M M M M = = = M = M = = = M = M M

= ----- M M M-

FGR mMechanisms: Thermal Release (11)


FGRMechanisms: Enhanced Release


= | Hi M M M M M M M M = = = -= M

=m =Mm== mi== ==M = M M=

FGR*Mechanisms: Additional Remarks

A2014 June 24th - GALILEO post-submittal meeting 37 AREVA

FGRMechanisms: Schematic Overview

I Steady state:]I- -

Transient

Gas escaping thepellet by recoiland knock-out

of atoms

ftlFathermal

Grain matrixswept by

grain boundaries

Fgrain growth

I---------------------------------------------

Diffusion of gas(Steady-stateor Transient)

Gas retained in matrix Gas diffused to(Booth solutions) grain boundaries

(intergranular bubbles)

Gas in Gas retained Saturationbubbles Xe solubility of grain boundary

limit (surface density

threshold)Intedinkage

FthermalFBu Enhancement steady-state I

transient

I---------------------------------------------

Partial openingof

Grain boundaries'

FBurt

--- - - - -


rn M - Mn--rn-- M M -M Mi M Mn -M M

M -- M-M M -M M M M M M -M -M-

FGREnhanced Release - Results (I)


FGREnhanced Release - Results (11)

=> Measured EPMA profiles are well reproduced by GALILEO FGR model.

2014 June 24th - GALILEO post-submittal meeting 40A

NREVA

m = - m - M - -M = M m m - m m m =

M M M M M nM Mn M MM M r M M -MM

FGRValidation

A41 AREVA2014 June 24th - GALILEO post-submittal meeting

Advanced Pellet Mechanical Models

ll Gaseous swelling model

00 Dish filling model

Oo Pellet mechanics

lo Original model GLOVD developed for transientconditions (driving clad strain)

Calibration process of the pellet deformationsdiffusion s

]incubation[ Gas ]strain fDish Pellet mechanicsFGR Swelling "LFilling during ramps

I check I


S= = n= M = = m = M M = = = = =

= m -= = = = = = = = = = = = = -= m

Gaseous Swelling Phenomenology

Oo Gaseous swelling refers to the portion of fuelswelling linked to porosity induced by fissiongases

K Mainly intergranular bubbles

" Does not include nanobubbles (included in solid swelling) atmacroscopical level

Po Closely linked to FGRI Evolution governed by FG diffusion towards bubbles

K Gaseous swelling occurs above the FG incubation threshold

Oo Mitigated by* Strong PCMI (hot pressing)

* Very high temperature (redensification)


Gaseous Swelling DatabasePp No direct access to measurements of gaseous swelling


M-m-- - -- -M----- --M M M

- - -- m ------- n-mm-mm-m- m- -

Gaseous SwellingModel Formulation

Oo Gaseous swelling equation rate


Gaseous SwellingResults

2014 June 24th - GALILEO post-submittal meetingA

46 AR EVA

M M M m M M-mm M M M M M M M M MM

M M M MM - M M -- -- -- M MM

Dish Filling


Pellet Mechanical Model


48 AR EVA

m M - - M - -M - - - -M m M M m

---- rn-rn-- m -. --- - --I - -

Cracking Model


The GLOVD Model


50 AREVA

M M M m I M M m-m-m- m

- M|----- M M --- M-- - -i

Clad Strain Validation (1/3)

Io Satisfactory results on the whole LID range


51 AREVA


l Satisfactory results for all types of fuel rods


M M no M -m M M M M M M M M M im M M M M

- - M - w M - - M-- - -M M M M - -M


0o Satisfactory results for all types of fuel


53 AREVA

Corrosion: Model Basis and Databases

Oo Separate oxidation models for each of the three claddingmaterials: Zry-4 and M5® for PWR and Zry-2 for BWR

]

A2014 June 24th - GALILEO post-submittal meeting 54 AREVA

M M M M-m - -M M M M m m M m M M M

-= - -= n -= -= M M M M M = = = = M=

Low Tin SR Zircaloy-4 CorrosionModel Formulation

A) post-submittal meeting 55 AR EVA2014 June 24th - GALILEe

Low Tin SR Zircaloy-4 CorrosionAccelerated Oxidation Rate at High Exposure

Validation Database - Measured Values


m m M M M M M m M M M M M M M M M M M

= M M - W = - M--- M -=m

Low Tin SR Zircaloy-4 CorrosionModel Calibration, Validation

Apost-submittal meeting 57 AR EVA2014 June 24th - GALILEC

Low Tin SR Zircaloy-4 Hydrogen Pick-UpModel Calibration, Validation


5a AREVA

- = M m M M -M m M M M M MMM

=-n M -M M -=- M = = = M

Recrystallized M5® CorrosionModel Formulation

Anittal meeting 59 AR EVA2014 June 24th - GALILEO post-subn

Recrystallized M5® CorrosionModel Calibration, Validation


6o AR EVA

---- M M=M mm - M to M MI

= M M= ==MmiM =M == wM = M =

Recrystallized M5® Hydrogen Pick-UpModel Formulation

A24th - GALILEO post-submittal meeting 61 AR EVA2014 June

Recrystallized M5® Hydrogen Pick-UpModel Calibration, Validation


MMH m - M MI M M m - -

- M m = m mm M m = M m -=

BWR Corrosion, Hydrogen, Crud00.[

]O Modern Zry-2 material has optimized microstructure that

minimizes nodular corrosion, however the lift-off databaseincludes older data points with higher nodular corrosion.

Oo A hydrogen model for Zircaloy-2 has been developed byAREVA separate from the GALILEO code and was submittedto the NRC in Nov. 2013.


BWR Uniform Corrosion

Oo Model validation, as shown later, is based on [measurements from (9x9) and (10x10) rodsirradiated in various commercial BWRs.

Oo It is applicable to both RXA and CWSR Zry-2claddings.


= m m M = - m - M m m m -

= = = = M = = M = M M M = = M = = = =

Zircaloy-2 Cladding CorrosionModel Formulation

Atal meeting 65 AR EVA2014 June 24th - GALILEO post-submit

BWR Zy-2 Uniform CorrosionValidation

Oo Despite the relativelylarge scatter, which iscommon for corrosionmodeling and which isaccounted for by modelparameter uncertainties,both figures show anoverall balanced result.


M - M m M M HI M M M -M M M M M M M M

M M M = w M m M m m M M m m m M M

Accounting for Crud in BWRAnalyses If

PopTypical crud layer thickness is part of the lift-off measurements on fuel rods irradiated inboth European and U.S. plants and Zr-2cladding in both CWSR and RXA metallurgicalcondition

0.[

]- A67 AR EVA2014 June 24th - GALILEO post-submittal meeting

Uniform Oxide and Crud ModelsShow Best-estimate Prediction of

Measured Lift-off Data


68 AREVA

= --------- -=i---i -M M

Oxidation and Hydriding: DesignCriteria Background

No Oxidation limits were established by considering wallthickness stress analysis constraints and operatingexperience regarding corrosion-induced failures

Corrosion-related failures not observed up to the established limitsbased on extensive operating experience.

Stress analyses conservatively support the amount of wall thinning atthe oxidation limits. Cyclic fatigue is also considered.

Corrosion limits coincide approximately with the hydrogen limits.

Oxdto liit Hyrgnlmt

Cladin tyePmS

BWR Zry-2 RXA [ ]

PWRM5RXA [ ] [ A2014 June 24th - GALILEO post-submittal meeting 69 AR EVA


Po Hydrogen limits

] for normal operation and AQOs, asrequested by NUREG-0800 SRP4.2

* Available mechanical test data were grouped according tometallurgical state - stress-relieved or recrystallized, andenvironmental conditions - unirradiated or irradiated, roomtemperature or elevated temperature.

* Data sources- AREVA mechanical test data on M5 cladding- Test program undertook by AREVA to gain data on RXA Zry-2 cladding: main

results described in AREVA paper 8538 at Topfuel 2013

- NFIR data: consists of SRA and RXA Zry-4 samples

* Most data include information regarding both uniform and total elongation


- ==M =M ===m ==mm ==

M M m M m M M M M M M M M M M M


Po Uniform strain, RXA data

0 Sharp reduction in ductility observed as a function of irradiation



lo Uniform strain, SRA data


m M- -m - -M-m -M M M MM m m M -

M--n M M M M M M M M M M nM M M M

Highlights of axial tensile and biaxial testson irradiated RXA Zry-2 cladding

Po Axial tensile tests:" All samples failed by ductile shear with the main fracture surface inclined 450 to the loading

direction

" Necking was noticed in all cases, at a higher degree in the low fast fluence samples, asexpected

" The residual strain to failure varied in the range of 4.3 % (HF and high H uptake) to 14.9 % (LF)

"2 The ultimate tensile strength (UTS) varied from 413 MPa to 714 MPa

lo The results from the hardening and relaxation tests aresummarized as follows:

" A total strain of 1.1% was achieved during the loading

"> At the end of the test after all relaxation steps, a total permanent strain of around 1.5% wasaccumulated

»• Ductility is maintained at the levels requiredby licensing criteria even for this elevatedhydrogen uptake level combined with highirradiation embrittlement


Hydrogen Uptake Model for Zry-2

Oo Hydrogen uptake criterion for Zry-2 cladding

< Hydrogen uptake model developed based on most recentdata acquired by AREVA and confirmed with non-AREVAdata - AREVA paper accepted at Topfuel 2014

tThe H uptake model was submitted in November 2013 in theframework of RAI response to RODEX4 RXA Supplement

+The GALILEO topical report makes reference to thisseparate submittal

AREVA plans to update GALILEO topical report to includethis model following NRC approval for use in RODEX4

*This allows for a single model* Review of implementation in GALILEO will be required


S- Mn - n= = = M-- = = = M m

m = = = M M - = = = M m m m - M-- - =

GALILEO MOX

OoModels

0oApplicability to NP MOX

loConversion

Hlmpact on Margin

2014 June 24th - GALILEO post-submittal meeting

A75 AR EVA

MOX Fuel ModelingIntroduction, Overview

OoAdapted MOX Fuel Models

Oo Specific MOX Fuel Models

Oo Key Material Properties

•[ ]


= =----- =----- = -M = = m

M- m -m M M M M M M M M M M M M M MM

MOX Fuel Modeling*


MOX Fuel ModelingI


78 AREVA

M m m =-- M = =m m m m m=m- M m

- - ~ - -- - - ------ - - ---

MOX Fuel Modeling

He balance = He volume after irradiation - Initial He volume (manufacturing)

STP: (00C/32°F - 101 3.25hPa/1 4.6959psi)

2014 June 24th - GALILEO post-submittal meeting 79 ARIEVA

MOX Fuel ModelingHelium Production Mechanisms (1/2)

lo He production originates from 3 different sources

* a decay of some of the actinides

* (n, a) reactions on 160

* Ternary fissions I Decreasing amount

ao a decay is a continuous process, depending on calendar elapsedtime, whereas (n, a) reactions on 160 and ternary fissions onlyoccur under irradiation

O Only MOX fuel can yield a significant amount of He, depending onthe initial isotopic composition and more particularly on the 241Amcontent (RG vs. NP MOX)

OP He production and by extension He behavior can be neglected forother fuel types (U02, U0 2-Gd2O3) AI.

2014 June 24th - GALILEO post-submittal meeting 8o AREVA

M- -M- Mm~ MON-

M M M M M M M -m- m -m n= M mM

MOX Fuel ModelingHelium Production Mechanisms (2/2)

AIth - GALILEO post-submittal meeting 81 AR EVA2014 June 24

MOX Fuel ModelingHelium Production Validation

• He production calculations are performed through the PRODHEL V2.2 module (CEA,France) embedded in the GALILEO code

]

N He production calculations have been successfully benchmarked with the ORIGEN-S code (ORNL, US) results [ I


M M Im M M M-M W W M'= mm M M M M -

= = M - m m - -o mm M M w M - -

MOX Fuel ModelingHelium Release Mechanisms (1/2)

ALEO post-submittal meeting 83 AR EVA2014 June 24th - GALl

MOX Fuel ModelingHelium Release Mechanisms (2/2)


M M M - m M M M w M m m M M M -,M m

= = - m - --= --M -m , M m = M

MOX Fuel ModelingHelium Release Multiscale Model

A E"0 post-submittal meeting

85 AR EVA2014 June 24th - GALILE

MOX Fuel ModelingHelium Release Model Calibration

6 A86 AREVA2014 June 24th - GALILEO post-submittal meeting

M M -m M MW S = = up M o M M g = M M-M

M = -I -I,-II I-II

MOX Fuel ModelingHelium Release Model Validation

A0 post-submittal meeting 87 AR EVA2014 June 24th - GALILE

MOX Fuel ModelingAdaptation for Helium Transient Release


M l M M no M m M M M -IM M m M MM

M- m M = M M m mm m M m m M 9 M M, = m

MOX Key Material PropertiesFuel Melting Point (1/2)

Aiittal meeting 89 AR EVA2014 June 24th - GALILEO post-subm

MOX Key Material PropertiesFuel Melting Point (2/2)

Oo Robustness of the MOX fuel melting temperature model andconservatism of its lower bound limit have been successfullybenchmarked against experimental data and reference modelsset-out from the literature

1) K. Yamamoto, T. Hirosawa, K. Yoshikawa, K. Mrozumi and S. Nomura, "Melting temperature and thermal conductivity

of irradiated mixed oxide fuel", Journal of Nuclear Materials 204 (1993) 85-92 A2014 June 24th - GALILEO post-submittal meeting 90 AR EVA

Mm fmm M 1111m--, m m - - -= M o M M m

m -m -m -m = m

Applicability to NPMOX

2014

AAREVA

Introduction

Po Difference between NP MOX and RG MOX

Po US NP MOX LTA Measurement in Database

lo US NP MOX LTA Performance Prediction

The fuel rod design and the fuel assembly design will providereliable and safe operation, comparable to that of equivalentlow- enriched uranium (LEU) designs.

9 A92 AR EVA2014 June 2 4 th - GALILEO post-submittal meeting

M M Mmm m W m -- m M n M M - m

- MmMM No mmm- m M m M M

Difference and Solution

Po1. Isotopics

0 Difference

NP plutonium has a greater concentration of fissionableisotopes and lower concentration of absorber isotopes.

K Approach

The difference in isotopes is modeled explicitly in Galileo fuelperformance code.Primary blend is more dilute for NP MOX to control localheating and fission gas release.


For information: Sample Un-irradiated Fuel Isotopic

- A94 AR EVA2014 June 2 4th - GALILEO post-submittal meeting

M O |- - -| m m M M n M M a

M M- M M M M~~m M-

For information: Plutonium Fissionsas a Fraction of Total Fissions

£

I

I

1.0

0.9

0.8

0.7

08

0.5

0.4

0.3

0.2

0.1

0.00 5 10 15 20 25 30 35

Bumup (GWdUThm)

40 45 50 55 60


95AREVA

Difference and Approach

0-2. Impurity

* Difference

NP plutonium will contain small amounts of gallium as astabilizer.

+ Approach

Manufacturing process: NP plutonium will be polished toremove the gallium prior to the MOX processing stage.Specification: The design impurity level for gallium for the NPMOX is similar to the current trace levels of gallium in LEUfuel.

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M" M m m M M- m m -M - m M

M M M M --- -M--- -MM M =

Difference and Solution

lo3. Microstructure

0 Difference

Very slight difference in thermal conductivity, fission gasrelease, fuel pellet swelling, and pellet radial powerdistribution.

0 Approach

U0 2 matrix that establishes the overall pellet microstructureis the same.NP MOX has a smaller total concentration of plutonium thanRG MOX to achieve similar reactivity.These parameters have been modeled in GALILEO.


US NP MOX LTA Measurements

t 4 lead test assemblies (LTAs) manufactured in Franceand irradiated at Catawba Unit 1

÷ Post-irradiation examination (PIE) performed at OakRidge National Laboratory

Non-destructive and destructive tests

Conclusion: NP MOX Measurements are within the rangeof the current database


m m m = M -= M = = m M M

--m wmm m M m mmm M- = M

US NP MOX LTA Measurements

2014 June 2 4 th - GALILEO post-submittal meeting

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NP MOX LTA PerformancePrediction

O Using GALILEO, predictions for the Catawba MOX LTAfuel rods have been compared with the measurementsfrom the hot cell PIE.

l- The GALILEO code is found to satisfactorily predict allphenomena. The predicted vs. measured behaviors forthe NP MOX are consistent with that of the RG MOX inthe verification and validation database.

" Fuel rod growth* Fuel stack growth* Fuel rod diameter* Fission gas release* Helium Balance* Free void volume* Internal gas pressure* Pellet density

A2014 June 2 4 th - GALILEO post-submittal meeting ioo AR EVA

M ý ý M M M M M M M - M M M m -- M M

i-R- -M M m - - -M

NP MOX LTA PerformancePrediction

Conclusion: FGR for NP MOX LTA is well predicted by GALILEO. The NP rods

are also consistent with the RG MOX data. A2014 June 2 4 th - GALILEO post-submittal meeting 101 AR EVA

Dry Conversion Process MOXIntroduction, Context

lo Current MOX manufacturing context:+ Industrial shift from ADU U0 2 feeding powder to DCP (dry conversion

process) U0 2 powder.

+ AREVA experience feedback is mainly based on ADU MOX.

Objective: demonstration))level vs. ADU MOXof DCP MOX in-pile equal performance


inmmin~minminminmm

m M m = - -M - M

Dry Conversion Process MOXDCP MOX vs. ADU MOX

> Overall equivalent phases surface distribution than reference>ADU MOX. No impact foreseen on in-pile performance. A

103 AR EVA2014 June 24th - GALILEO post-submittal meeting

Dry Conversion Process MOXDCP MOX vs. ADU MOX

No Same expected in-pile performances:+ No major microstructural specificities of DCP MOX

No foreseen impact of DCP U0 2 feeding powder on:" Thermal conductivity" Melting point" Densification & Swelling" Fission gas release" Pellet cladding interaction (PCI) behavior" Reactivity initiated accident (RIA) behavior

lo Positive experience feedback from DCP MOX irradiationfollow-up program - no impact of DCP U0 2 feeding powderon base-irradiation performances relative to:

" Rod and fuel stack dimensional evolution" Fuel density" FG and helium release

Next objective: demonstration of the ability of GALILEO to predict DCPMOX behavior A


= ý M = M = = M M = -M- MMMM MMM

- - - -- - - - - m - m m -

Dry Conversion Process MOXGALILEO Predictions vs. Measurements

Io Fuel rods dimensional behavior


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lo Fuel pellet density evolution

2014 June 24th - GALILEO post-submittal meeting1 A106 AR EVA

= M = -= -=n M - -= ==M===M M

= ------- = = -=- ==N


Pp Puncturing results


Dry Conversion Process MOXConclusions -

lo DCP MOX as-fabricated properties and microstructuralfeatures are equivalent to those of standard ADU MOX.

4 Therefore in-pile performances are expected to be the same.

lo Results from the DCP MOX irradiation follow-up programlead to the conclusion of the non-impact of DCP U0 2 feedingpowder on MOX in-pile performance under base-irradiationconditions.

lo GALILEO prediction results of DCP MOX fuel rods are in thesame scatter as standard ADU MOX fuel from the experiencefeedback database.

))GALILEO is able to correctly predict the in-pile behaviorof DCP MOX fuel rods.


M m M M M M M M M M M M M-

M - m M - m M m M m m m m m M - m M

Impact of MOX on Fuel RodAnalyses

Oo Expected Impact of MOX on fuel rod analyses

Alog AR EVA2014 June 24th - GALILEO post-submittal meeting

Impact of MOX on Fuel RodAnalyses

Oo Differences in results from application examples* For BWRs, an application example for MOX fuel shows similar

results to the corresponding U0 2 case

* For PWRs, an application example for MOX fuel also showssimilar results to the corresponding U0 2 case except for lowermargin to the collapse criterion (due to a combined effect ofhigher LID and densification for the MOX fuel)

* In general, the MOX fuel is designed by taking intoconsideration fuel differences

00 In summary, the application example cases do not showsignificant differences in results between MOX and U0 2 fuelbecause of fuel design and core design strategies


M MI M M M M M M n M M M M M

M m MMm m M Mm m m M M M M

Summary

lo The GALILEO topical report presents of a state-of-the-art fuel rod code and methodology

Applicable to PWRs and BWRs<0 Applicable to U0 2 and MOXKApplicable to all AREVA cladding and fuel typesK Includes all observed phenomena, including fuel thermal

conductivity reduction with burnup2 Code is backed by extensive calibration and validation

databaseK Utilizes a realistic methodology

lo Replaces legacy codes RODEX2I2A, TACO3,GDTACO

loAdds hydrogen models to address future NRCchanges to LOCA and control rod ejection criteria


NRC Review Process

Pp Audits

Pp RAIs

1 A112 AREVA2014 June 2 4 th - GALILEO post-submittal meeting

M M M M M M M M M m m m m M M M M M

M M M M M M M M M M I M M M M M M

Next Steps

Oo Update of GALILEO topical report to include Zr-2hydrogen model - upon RODEX4 approval

.Audit(s)

0 One or more audits will facilitate the NRC review

OoRAI

K One round of RAIs would make the review efficient

Op SER

0 SER Requested by December 31, 2015


Acronyms/NomenclatureADUAOOB&WBWR

CECEACWSRDCPEPUFEFGFGRHPUFIDL/DLEULHGRLOCALTAMOX

NPNRCOD

Ammonia DiuranateAnticipated Operational OccurrenceBabcock and WilcoxBoiling Water ReactorCombustion EngineeringFrench Atomic Energy CommissionCold Worked Stress RelievedDry Conversion ProcessExtended Power UprateFinite ElementFission GasFission Gas ReleaseHydrogen Pick-up FractionInner DiameterLengthlDiameter

Low-Enriched UraniumLinear Heat Generation RateLoss of Coolant AccidentLead Test AssemblyMixed OxideNon ProliferationNuclear Regulatory Commission

Outer Diameter

PCIPCMIPIEPIRT

PWRRAIRGRIARXRXASRATCDTD

Pellet Cladding InteractionPellet Cladding Mechanical Interaction

Post-Irridiation ExaminationPhenomena Identification and RankingTablePressurized Water ReactorRequest for Additional InformationReactor GradeReactivity Insertion AccidentRecrystallizedRecrystallizedStress Relieved AnnealedThermal Conductivity DegradationTheoretical Density

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Mmn M M M M M M M M m m M - M

galileo fuel rod performance code and methodology for bwrs ... · " galileo was calibrated to...

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