Uncertainty Quantification of Calculated Temperatures for the U.S. Capsules in the AGR-2 Experiment

Lybeck, Nancy¹  Einerson, Jeffrey J.¹  Pham, Binh T.¹  Hawkes, Grant L.¹ 

[1] Idaho National Lab. (INL), Idaho Falls, ID (United States)

关键词: Advanced Gas Reactor;    Advanced Reactor Technology;    Advanced Test Reactor;    Nuclear Data Management and Analysis Syste;    post-irradiation examination;    tristructural-isotropic;   

DOI  :  10.2172/1184085
RP-ID  :  INL/EXT-15-34587
PID  :  OSTI ID: 1184085

学科分类：核能源与工程

美国|英语

来源: SciTech Connect

【 摘 要 】

A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN-3636). The AGR-2 test was inserted in the B-12 position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in June 2010 and successfully completed irradiation in October 2013, resulting in irradiation of the TRISO fuel for 559.2 effective full power days (EFPDs) during approximately 3.3 calendar years. The AGR-2 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS) (Pham and Einerson 2014). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as-run thermal analysis has been performed separately on each of four AGR-2 U.S. capsules for the entire irradiation as discussed in (Hawkes 2014). The ABAQUS code???s finite element-based thermal model predicts the daily average volume-average fuel temperature and peak fuel temperature in each capsule. This thermal model involves complex physical mechanisms (e.g., graphite holder and fuel compact shrinkage) and properties (e.g., conductivity and density). Therefore, the thermal model predictions are affected by uncertainty in input parameters and by incomplete knowledge of the underlying physics leading to modeling assumptions. Therefore, alongside with the deterministic predictions from a set of input thermal conditions, information about prediction uncertainty is instrumental for the ART program decision-making. Well defined and reduced uncertainty in model predictions helps increase the quality of and confidence in the AGR technical findings.