​​​​Reports - Fuel Qualification​

Status of Modifications to the AGR-3/4 Fission Product Transport ModelFuel Qualification
A one-dimensional (1D) finite-element model of the AGR 3/4 experiment fission product distributions based on the Multiphysics Object-Oriented Simulation Environment (MOOSE) framework has been revised and implemented within BISON, with improvements which allow for detailed temperature histories to be used for analyses. Empirically determined concentration profiles and ring inventories from the AGR-3/4 experiment have been compiled for comparison purposes. Ongoing efforts to build fission product diffusion models which can describe the applicable physics for isotopic concentration profiles in each AGR-3/4 capsule are discussed, as well as the suitability of each isotopic concentration profile in each capsule for obtaining transport parameters.
74703_Investigation and Demonstration of Reliability Target Allocation to Support Reliability and Integrity Management ProgramFuel Qualification
Nuclear energy is the most reliable and environmentally sustainable energy source available today. In the United States (U.S.), nuclear-generated power accounts for approximately 20% of total electricity and over 55% of clean energy. New advanced reactors have enormous potential to help further decarbonize the energy market, enhance grid resiliency, create new jobs, and build a stronger economy. More than 50 new reactors are being developed in the U.S., and the federal government realizes an urgent need to deploy nuclear technologies to meet the country’s energy, environmental, and national security goals. As such, the U.S. Department of Energy (DOE) launched multiple programs to support advanced reactor deployment. The research described in this report explores implementation strategies for the Reliability and Integrity Management Program that directly supports the DOE goal to enable the near-term deployment of the advanced reactor technologies. The project is conducted under the Regulatory Development Program for advanced reactors sponsored by the DOE.
74505_PARFUME/BISON Fission Product Release Predictions versus AGR-3/4 Heating Test MeasurementsFuel Qualification
The fuel performance modeling codes PARFUME (PARticle FUel ModEl) and BISON were used to predict the release of fission products silver, cesium, and strontium from as-irradiated fuel compacts containing tristructural isotropic (TRISO) coated particles during heating tests post irradiation. The AGR-3/4 fuel compacts were irradiated as part of the third and fourth series of planned experiments to support the Advanced Gas Reactor (AGR) program. The heating tests were conducted at temperatures between 1200°C and 1700°C to simulate reactor accident conditions. The measured fission product release fractions from the heating tests were compared to modeling predictions calculated by PARFUME and BISON to evaluate how the codes compare to experimental results. Comparisons between the experimental measured fission product release fractions from silver, cesium and strontium indicate that both modeling codes overpredict the fission product release fractions demonstrating that the diffusivities used in the codes are overestimated. This results in a conservative estimate predicted by the codes when evaluating the fission product release relative to experimental data as it pertains to silver, cesium, and strontium.
73074_AGR-5/6/7 Thermal Model with Non-uniform Gas GapsFuel Qualification
Fuel compact temperatures are a crucial factor in assessing irradiation performance of the Tristructural isotropic fuel particles. In the absence of direct measurement, fuel compact temperatures were calculated using a three-dimensional finite element thermal model, which is subject to simulation uncertainty. The most dominant factor in uncertainty of calculated fuel temperature is the gas gap uncertainty due to the nub-to-shell clearance because of fabrication error. A revision to the thermal model was made to examine the most probable offset position for four different dates of interest. The offset position options varied in magnitude and azimuthal direction of offset of the holder top and bottom position. The best-fit offset of the holder is estimated based on the minimum root mean square error of residuals for all operational thermocouples (TCs). From these results, the following conclusions were made: 1) During earlier cycles (162A – 164A) when numerous TCs were still operational, the best-fit offset distance varied in range [0.002 – 0.0035 in.] for both the top and bottom holder while offset azimuthal direction varied widely, especially for the holder bottom. 2) Holder offset led to slightly lower Capsule 1 average temperature, but wider temperature variation (lower minimum and higher peak fuel temperatures).
72036 R1_Review and Assessment of NGNP PIRTs for TRISO and HTGR TechnologiesFuel Qualification
The main objective of this technical report is to ensure that research and development (R&D) needs are identified to address the significant (highly ranked) technical challenges related to TRISO-coated particle fuel, high-temperature gas-reactor (HTGR) technologies, and other TRISO-related advanced designs by recognizing the existing foundation of identified R&D needs and augmenting that foundation with insights drawn from current TRISO-related research results and R&D needs related to novel applications of TRISO-related technologies that extend beyond the traditional HTGR designs.
Kernel Buffer Volume Fraction Margin of the AGR Designed Fuel ParticleFuel Qualification
Modeling results used to assess the fuel performance of the TRISO-coated fuel particles as a function of kernel/buffer volume fraction include SiC tangential stress, formation of the buffer/IPyC gap, particle temperature profile, internal particle pressure, fission gas released from the kernel, probability of fuel particle failure, and fission product diffusion.
Advanced Gas Reactor Fuel Specification Technical BasesFuel Qualification
The technical bases for the TRISO-coated particle fuel specifications used by the AGR Program during its fabrication process development and fuel qualification efforts are provided based on historical HTGR fabrication experience in the U.S. and Germany and improvements and insights gained during execution of the AGR Program. The technical bases are provided for specified properties of the kernel, the TRISO coating layers, the fuel particle, and fuel compact in terms of fabricability considerations, in-pile fuel performance, and fission product release under normal and off-normal conditions.
AGR-5/6/7 Irradiation Disassembly and Metrology First LookFuel Qualification
The Advanced Gas Reactor (AGR) Fuel Development and Qualification Program was established to perform research and development on tristructural isotropic (TRISO)-coated particle fuel to support deployment of high-temperature gas-cooled reactors (HTGRs), which are graphite-moderated nuclear reactors cooled with helium. This work continues as part of the Advanced Reactor Technologies (ART) TRISO Fuel Program. The overarching program goal is to provide a baseline fuel qualification data set to support licensing, deployment, and operation of HTGRs in the United States. To achieve these goals, the program includes fuel fabrication, irradiations of TRISO fuels and high-temperature materials (e.g., graphite), safety testing and post-irradiation examination (PIE), fuel performance modeling, and fission product transport and source term determination. The ART AGR program has conducted four distinct fuel irradiation experiments in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). The subject of this report is AGR-5/6/7, the final qualification test of AGR TRISO fuel made entirely at the engineering scale.
AGR-5/6/7 Irradiation Test Final As-Run ReportFuel Qualification
This document presents the as-run analysis of the AGR-5/6/7 irradiation experiment. AGR-5/6/7 is the last of a series of experiments conducted in the ATR at INL in support of the development and qualification of tri-structural isotropic low-enriched fuel for use in high-temperature gas-cooled reactors.
Automated Internal Energy Calibration by OnTheFly for AGR-5/6/7Fuel Qualification
The software program, OnTheFly, was developed at INL to keep HPGe detectors energy calibrated during very long experiments. Over time, spectra produced from a HPGe detector will slowly stretch or contract, causing the energy calibration to change. If the energy calibration changes too much, it will cause energy lines to be misidentified.
As-Run Thermal Analysis for the AGC-4 Experiment Irradiated in the ATRFuel Qualification
The Advanced Graphite Capsule (AGC) irradiation experiment will provide irradiation creep rate data for the new graphite proposed for the Next Generation Nuclear Plant (NGNP) program. The fourth experiment in the series (AGC-4) was designed to irradiate various types of graphite specimens at a temperature of 900 ºC and targeted displacements per atom (DPA) of 6.
AGR-5/6/7 Data Qualification Report for ATR Cycles 162B through 168AFuel Qualification
This report provides the qualification status of experimental data for the AGR-5/6/7 fuel irradiation. AGR-5/6/7 was conducted in the ATR at INL in support of the development and qualification of TRISO low-enriched fuel for use in high-temperature gas-cooled reactors.
Advanced Microscopy Report on UCO Fuel Kernels from Selected AGR-1 and AGR-2 ExperimentsFuel Qualification
A variety of neutron irradiation experiments were completed at INL on TRISO coated particles contained in a graphitic matrix as part of the Advanced Gas Reactor (AGR) fuel development and qualification program. Although the initially advanced microscopy and microanalysis studies on AGR-1 particles focused predominantly on the SiC layer's role as the main fission-product containment, studies were further expanded to evaluate UCO kernels of selected AGR-1 and AGR-2 coated particles.
UCO TRISO-Coated Particle Fuel Performance—Topical Report EPRI-AR-1(NP)-AFuel Qualification
Uranium Oxycarbide (UCO) Tristructural Isotropic (TRISO)-Coated Particle Fuel Performance—Topical Report EPRI-AR-1(NP)-A
Comparison between PARFUME and Bison Using the AGR-2 Irradiation ExperimentFuel Qualification
This report documents comparisons between Fuel Model (PARFUME) model predictions versus Bison for selected compacts from the second irradiation test of the Advanced Gas Reactor (AGR) program that occurred from June 2010 to October 2013 in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). PARFUME is a fuel performance analysis and modeling code, used for evaluating gas-reactor tristructural isotropic (TRISO) coated particle fuel for prismatic, pebble bed, plate, and cylindrical type fuel geometries.
Radial Deconsolidation and Leach-Burn-Leach of AGR-3/4 Compact 1-4 and 10-4Fuel Qualification
The Advanced Gas Reactor (AGR) Fuel Development and Qualification Program third and fourth irradiation experiments (AGR-3/4), originally planned as separate tests, were combined in one test train for irradiation in the Advanced Test Reactor at Idaho National Laboratory (INL).
AGR-5/6/7 Experiment Monitoring and Simulation ProgressFuel Qualification
Advanced Gas Reactor (AGR)--5/6/7 is the last of a series of AGR experiments conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tri-structural isotropic (TRISO) low-enriched fuel for use in high temperature gas-cooled reactors. The test train contains five separate capsules that are independently controlled and monitored. Each capsule contains multiple 12.51 mm long compacts filled with low-enriched uranium carbide/oxide (UCO) TRISO fuel particles.
Comparison of Fission Product Release Predictions using PARFUME with Results from the AGR-2 Irradiation ExperimentFuel Qualification
The PARFUME (PARticle FUel ModEl) code was used to predict fission product release from tristructural isotropic (TRISO) coated fuel particles and compacts during the second irradiation experiment (AGR-2) of the Advanced Gas Reactor Fuel Development and Qualification Program.
AGR-5/6/7 Post-Irradiation Examination PlanFuel Qualification
This plan describes the PIE activities to be carried out on AGR-5/6/7 fuel and the non-fuel components of the AGR-5/6/7 irradiation test train. PIE of AGR-5/6/7 fuel and test train components will provide data on fuel performance over a range of irradiation conditions (e.g., burnup, neutron fluence, and temperature), test fuel under postulated accident conditions, and support development of fuel performance and fission product transport models.
NDMAS System and Process DescriptFuel Qualification
The DOE has made a significant investment in research to develop the next generation of reactor technologies as well as to improve the performance and lengthen the life cycle of existing nuclear reactors. Data collected to demonstrate new concepts may also be used in the future to support licensing of these technologies. Provenance of these data must be preserved. The NDMAS was established to manage and preserve data collected by fuels and materials research conducted by the high-temperature, gas-cooled reactor program.
Safety Testing and Destructive Examination of AGR-2 UO2 Compact 3-1-1Fuel Qualification
Post-irradiation examination and elevated-temperature safety testing are being performed on compacts from the Advanced Gas Reactor Fuel Development and Qualification Program’s AGR-2. The compacts in the AGR-2 irradiation experiment held either tristructural isotropic (TRISO)-coated particles containing uranium oxide fuel kernels or TRISO-coated particles containing fuel kernels with both uranium carbide and uranium oxide phases.
https://art.inl.gov/ReportsFolder/MaterialPropertiesReport.pdfFuel Qualification
The purpose of this study is to identify the material properties that have the largest impact on the failure probability of TRISO-coated fuel particles under irradiation. The TRISO fuel performance modeling code PARFUME was used to assess the material properties that have the main influence on the probability of failure of the silicon carbide (SiC) layer of TRISO fuel particles.
AGR-2 Irradiation Test Final As-Run ReportFuel Qualification
The objectives of the AGR 2 experiment are to: 1) Irradiate UCO  and UO2 fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR 1 test and other project activities. 2) Provide irradiated fuel samples for PIE and safety testing. 3) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance.