Pitch Variation Experiments in Water-Moderated Square-Pitched U(6.90)O2 Fuel Rod Lattices with Fuel to Water Volume Ratios Spanning 0.08 to 0.67
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Naval Nuclear Lab. (NNL), Idaho Falls, ID (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Inst. de Radioprotection et de Sûrete Nucleaire (ISRN), Fontenay-aux-Roses (France)
The US Department of Energy (DOE) Nuclear Energy Research Initiative funded the design and construction of the Seven Percent Critical Experiment (7uPCX) at Sandia National Laboratories. The start-up of the experiment facility and the execution of the experiments described here were funded by the DOE Nuclear Criticality Safety Program. The 7uPCX is designed to investigate critical systems with fuel for light water reactors in the enrichment range above 5 % 235U. The 7uPCX assembly is a water-moderated and -reflected array of aluminum-clad square-pitched U(6.90 %)O2 fuel rods. Other critical experiments performed in the 7uPCX assembly are documented in LEU-COMP-THERM-078, LEU-COMP-THERM-080, LEU-COMPTHERM- 096, LEU-COMP-THERM-097, and LEU-COMP-THERM-101. The fuel used in these experiments was fabricated using unirradiated 6.90 % enriched UO2 fuel pellets from fuel elements designed to be used in the internal nuclear superheater section of the Pathfinder boiling water reactor operated in South Dakota by the Northern States Power Company in the 1960s. The fuel elements were obtained from The Pennsylvania State University where they had been stored for many years. The fuel pellets in those fuel elements were removed from the original Incoloy cladding and reclad in 3003 aluminum tubes and end caps for use in the experiments reported here. The purpose of these experiments was to measure the effects of decreasing the fuel-to-water volume ratio on the critical array size. This was accomplished by removing fuel rods from fully fueled configurations, effectively increasing the pitch of the fuel arrays in the assembly. The fuel rod pitch variations provided assembly configurations that ranged from strongly undermoderated to slightly overmoderated.
- Research Organization:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA)
- DOE Contract Number:
- AC04-94AL85000; A0003525
- OSTI ID:
- 1671168
- Report Number(s):
- SAND-2020-10742R; 691197; TRN: US2204350
- Resource Relation:
- Related Information: Nuclear Criticality Safety Program
- Country of Publication:
- United States
- Language:
- English
Similar Records
Pitch Variation Experiments in Water-Moderated Square-Pitched U(6.9)O2 Fuel Rod Lattices with Fuel to Water Volume Ratios Spanning 0.08 to 0.67
Titanium and Aluminum Rod-Replacement Experiments in Fully-Reflected 6.90% Enriched UO{sub 2} Fuel Rod Lattices