Analysis of Decay Heat Measurements for BWR Fuel Assemblies

摘要

Due to advances in fuel and core design and fuel cycle optimization, the burnup range of assemblies discharged from commercial reactors has been steadily extended to higher values. In order to determine the accuracy of decay heat predictions for high-burnup spent fuel, current analysis methodologies and computer codes need to be validated to cover a larger enrichment and burnup domain. The scarcity of available experimental measurements required for this validation makes the endeavor rather difficult. An experimental program recently initiated at the Central Interim Storage Facility (CLAB) in Sweden to perform calorimeter measurements on full-length assemblies provides valuable thermal decay heat data for both BWR and PWR assembly designs over a large burnup range. Oak Ridge National Laboratory (ORNL), a collaborator in this program through support from the U.S. Nuclear Regulatory Commission (NRC), is evaluating the measurements with the SCALE 5 computer code system.