FRAPCON/FRAPTRAN Users Group Meeting:

Recent Code Updates and Future Plans

Ken GeelhoodWalter Luscher

Carl BeyerPacific Northwest National Laboratory

September 7, 2012

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Outline

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Current code versionsChanges made so far

FRAPCON-3.5FRAPTRAN 1.5FRAPCON-ARM

Recent code benchmarksUpcoming Changes

FRAPCON-3.5FRAPTRAN 1.5

Upcoming ActivitiesNext Code Release

Current Code Versions

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FRAPCON-3.4aCode Description: NUREG/CR-7022 Vol.1Integral Assessment: NUREG/CR-7022 Vol.2

FRAPTRAN 1.4Code Description: NUREG/CR-7023 Vol.1Integral Assessment: NUREG/CR-7023 Vol.2

Consistent material properties in both codesMaterial Property Correlations: NUREG/CR-7024

Documentation available on: http://frapcon.labworks.org/

The ongoing development of FRAPCON-3 and FRAPTRAN is sponsored by the U.S. NRC

Changes Made to Date:FRAPCON-3.5

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Model improvementsModel for gaseous swelling added to better predict cladding hoop strain during high burnup ramp tests

New CapabilitiesAbility to model pellets with chamfers was addedAbility to input variable axial node lengths was addedMore output was added for stochastic analysis

Error correctionBetter error messages were added to help debug input fileDefault values in manual and code were matched

FRAPCON-3.5 model Improvements:Gaseous Swelling

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Gaseous swelling observed between 960˚C and 1832˚C

Model is linearly phased in between 40 and 50 GWd/MTU and fully applied above 50 GWd/MTU

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Mogensen Data at 39 GWd/MTU Mogensen Data at 33 GWd/MTU Gaseous Swelling Model

FRAPCON-3.5 model Improvements:Gaseous Swelling

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New model improves predictions of ramp hoop strain at high burnup

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Rod Average Burnup, GWd/MTU

Original Assessment Cases Original Assessment ModSCIP Long Hold Times SCIP Long ModSCIP Short Hold Times SCIP Short ModB&W Stud Long Hold Time B&W Mod

Changes Made to Date:FRAPTRAN 1.5

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Model improvementsChanges made to how the code does ballooning calculationsDouble sided oxidation changed

New CapabilitiesNumber of input coolant zones changed from 10 to 20Interpolate between input coolant zones for axial nodesAbility to specify an external plenum volumeMaximum number of axial nodes changed from 25 to 150

Error correctionLower bound for Cathcart/Pawel model changed from 1000K to 1073KErrors in heat transfer correlations correctedBetter error messages were added to help debug input fileDefault values in manual and code were matchedError in fill gas composition after rupture

FRAPTRAN 1.5 model Improvements:Ballooning Model

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More strain values are output to FRAPTRAN

Thinned cladding used to calculation ECRIncreased diameter used to calculation metal water reaction energy

FRAPTRAN 1.5 model Improvements:ID Oxidation

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New options addedFRAPTRAN 1.4

ID oxidation only calculated in burst area after burst

FRAPTRAN 1.5Option to calculate ID oxidation one of two ways

FRAPTRAN 1.4 method

-or-Calculate for all nodes regardless of burst if nodal burnup exceeds value set by user

Changes made to Date:Uncertainty Analysis with FRAPCON-ARM

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Stochastic framework capable of running many realizations of FRAPCON-3.4 varying:

Manufacturing uncertaintiesModel uncertaintiesPower uncertainties

Package reads data from each realization and compiles distributions for each output of interest. Allows staff to validate vendor predictions of nominal and upper tolerance limit for various code outputs.Methodology does not rely on assumptions of normality for input or output distributions as the RMS methods typically used in industry do.

Uncertainty Analysis with FRAPCON-ARMInput

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Uncertainty Analysis with FRAPCON-ARMInput

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Uncertainty Analysis with FRAPCON-ARMOutput

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Calculated Upper Tolerance Limits

Output distributions Inputs and outputs for each realization

Uncertainty Analysis with FRAPCON-ARMOutput

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Output vs. InputTest for Normality

Recent Code Benchmarks

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IFA-699 Subject: CreepPresented at: 2011 EHPG Meeting

SCIP, TRANS RAMP IVSubject: FGR during short hold time rampsPresented at: Not publically presented

Hydrogen pickup modelsPresented at: 2011 Water Reactor Fuel Performance Meeting

IRSN RIA BenchmarksHigh burnup RIA tests

FUMEX-IIIParticipated with TRACTEBEL and NRI

Upcoming Changes:FRAPCON-3.5

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Model improvementsUpdates to implementation of creep model in FRAPCONUpdates to better predict BOL temperatures

New CapabilitiesAxial variation in enrichment

Axial variation in Gd2O3 contentAbility to specify axial regions with and without a central holeImproved ability to model refabricated rodlets

Model base irradiation and create restart fileModel test on refabricated rod using selected axial nodes from restart

Excel input generator updates and improvements to match FRAPCON-3.5 change

Possible support of SNAP within 1-2 years

Upcoming Changes:FRAPTRAN 1.5

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Review of FLECHT reflood correlations in code and comparison to FLECHT data setAbility to model pellets with chamfersExcel input generator updates and improvements to match FRAPTRAN 1.5 changes

Possible support of SNAP within 1-2 years

Upcoming Activities

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Peer ReviewNeed at least five members of Users GroupPeer review should identify:

Code deficienciesSuggestions for code improvements

Peer review will begin shortly following this meetingSign up now to participateOther members will be contacted by e-mail

New Code Release

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Plans to release FRAPCON-3.5 and FRAPTRAN 1.5 early 2014Documentation?

NUREG/CR?Web documentation?