FRAPCON/FRAPTRAN Users Group Meeting: Recent Code Updates and Future Plans Ken Geelhood Walter Luscher Carl Beyer Pacific Northwest National Laboratory September 7, 2012 1 Outline Current code versions Changes made so far FRAPCON-3.5 FRAPTRAN 1.5 FRAPCON-ARM Recent code benchmarks Upcoming Changes FRAPCON-3.5 FRAPTRAN 1.5 Upcoming Activities Next Code Release 2 Current Code Versions FRAPCON-3.4a Code Description: NUREG/CR-7022 Vol.1 Integral Assessment: NUREG/CR-7022 Vol.2 FRAPTRAN 1.4 Code Description: NUREG/CR-7023 Vol.1 Integral Assessment: NUREG/CR-7023 Vol.2 Consistent material properties in both codes Material 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 3 Changes Made to Date: FRAPCON-3.5 Model improvements Model for gaseous swelling added to better predict cladding hoop strain during high burnup ramp tests New Capabilities Ability to model pellets with chamfers was added Ability to input variable axial node lengths was added More output was added for stochastic analysis Error correction Better error messages were added to help debug input file Default values in manual and code were matched 4 FRAPCON-3.5 model Improvements: Gaseous Swelling Gaseous swelling observed between 960˚C and 1832˚C 8.0 7.0 6.0 Swelling, DV/V (%) 5.0 4.0 3.0 2.0 1.0 0.0 0 500 1000 1500 2000 2500 Temperature (°C) Mogensen Data at 39 GWd/MTU Mogensen Data at 33 GWd/MTU Gaseous Swelling Model Model is linearly phased in between 40 and 50 GWd/MTU and fully applied above 50 GWd/MTU 5 FRAPCON-3.5 model Improvements: Gaseous Swelling New model improves predictions of ramp hoop strain at high burnup Predicted minus Measured Plastic Strain Incrament, % 1.5 6 1 0.5 0 -0.5 -1 -1.5 -2 15 25 35 45 55 65 75 Rod Average Burnup, GWd/MTU Original Assessment Cases SCIP Long Hold Times SCIP Short Hold Times B&W Stud Long Hold Time Original Assessment Mod SCIP Long Mod SCIP Short Mod B&W Mod 85 Changes Made to Date: FRAPTRAN 1.5 Model improvements Changes made to how the code does ballooning calculations Double sided oxidation changed New Capabilities Number of input coolant zones changed from 10 to 20 Interpolate between input coolant zones for axial nodes Ability to specify an external plenum volume Maximum number of axial nodes changed from 25 to 150 Error correction 7 Lower bound for Cathcart/Pawel model changed from 1000K to 1073K Errors in heat transfer correlations corrected Better error messages were added to help debug input file Default values in manual and code were matched Error in fill gas composition after rupture FRAPTRAN 1.5 model Improvements: Ballooning Model More strain values are output to FRAPTRAN Thinned cladding used to calculation ECR Increased diameter used to calculation metal water reaction energy 8 FRAPTRAN 1.5 model Improvements: ID Oxidation New options added FRAPTRAN 1.4 ID oxidation only calculated in burst area after burst FRAPTRAN 1.5 Option to calculate ID oxidation one of two ways FRAPTRAN 1.4 method -orCalculate for all nodes regardless of burst if nodal burnup exceeds value set by user 9 Changes made to Date: Uncertainty Analysis with FRAPCON-ARM Stochastic framework capable of running many realizations of FRAPCON-3.4 varying: Manufacturing uncertainties Model uncertainties Power 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. 10 Uncertainty Analysis with FRAPCON-ARM Input 11 Uncertainty Analysis with FRAPCON-ARM Input 12 Uncertainty Analysis with FRAPCON-ARM Output Output distributions Inputs and outputs for each realization Calculated Upper Tolerance Limits 13 Uncertainty Analysis with FRAPCON-ARM Output Output vs. Input 14 Test for Normality Recent Code Benchmarks IFA-699 Subject: Creep Presented at: 2011 EHPG Meeting SCIP, TRANS RAMP IV Subject: FGR during short hold time ramps Presented at: Not publically presented Hydrogen pickup models Presented at: 2011 Water Reactor Fuel Performance Meeting IRSN RIA Benchmarks High burnup RIA tests FUMEX-III Participated with TRACTEBEL and NRI 15 Upcoming Changes: FRAPCON-3.5 Model improvements Updates to implementation of creep model in FRAPCON Updates to better predict BOL temperatures New Capabilities Axial variation in enrichment Axial variation in Gd2O3 content Ability to specify axial regions with and without a central hole Improved ability to model refabricated rodlets Model base irradiation and create restart file Model 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 16 Upcoming Changes: FRAPTRAN 1.5 Review of FLECHT reflood correlations in code and comparison to FLECHT data set Ability to model pellets with chamfers Excel input generator updates and improvements to match FRAPTRAN 1.5 changes Possible support of SNAP within 1-2 years 17 Upcoming Activities Peer Review Need at least five members of Users Group Peer review should identify: Code deficiencies Suggestions for code improvements Peer review will begin shortly following this meeting Sign up now to participate Other members will be contacted by e-mail 18 New Code Release Plans to release FRAPCON-3.5 and FRAPTRAN 1.5 early 2014 Documentation? NUREG/CR? Web documentation? 19