Standalone BISON Fuel Performance Results for Watts Bar Unit 1, Cycles 1-3

Technical Report · Mon Mar 07 04:00:00 EST 2016

DOI:https://doi.org/10.2172/1248783· OSTI ID:1248783

Clarno, Kevin T. ^[1]; Pawlowski, Roger ^[2]; Stimpson, Shane ^[1]; Powers, Jeffrey ^[1]

---

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

The Consortium for Advanced Simulation of Light Water Reactors (CASL) is moving forward with more complex multiphysics simulations and increased focus on incorporating fuel performance analysis methods. The coupled neutronics/thermal-hydraulics capabilities within the Virtual Environment for Reactor Applications Core Simulator (VERA-CS) have become relatively stable, and major advances have been made in analysis efforts, including the simulation of twelve cycles of Watts Bar Nuclear Unit 1 (WBN1) operation. While this is a major achievement, the VERA-CS approaches for treating fuel pin heat transfer have well-known limitations that could be eliminated through better integration with the BISON fuel performance code. Several approaches are being implemented to consider fuel performance, including a more direct multiway coupling with Tiamat, as well as a more loosely coupled one-way approach with standalone BISON cases. Fuel performance typically undergoes an independent analysis using a standalone fuel performance code with manually specified input defined from an independent core simulator solution or set of assumptions. This report summarizes the improvements made since the initial milestone to execute BISON from VERA-CS output. Many of these improvements were prompted through tighter collaboration with the BISON development team at Idaho National Laboratory (INL). A brief description of WBN1 and some of the VERA-CS data used to simulate it are presented. Data from a small mesh sensitivity study are shown, which helps justify the mesh parameters used in this work. The multi-cycle results are presented, followed by the results for the first three cycles of WBN1 operation, particularly the parameters of interest to pellet-clad interaction (PCI) screening (fuel-clad gap closure, maximum centerline fuel temperature, maximum/minimum clad hoop stress, and cumulative damage index). Once the mechanics of this capability are functioning, future work will target cycles with known or suspected PCI failures to determine how well they can be estimated.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Consortium for Advanced Simulation of LWRs (CASL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1248783
• Report Number(s): ORNL/TM--2015/776; CASL-U--2015-1010-001; NT0304000; NEAF343; CASL-U-2015-1010-001
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
97 MATHEMATICS AND COMPUTING
B CODES
DAMAGE
FAILURES
FUEL PINS
FUEL-CLADDING INTERACTIONS
HEAT TRANSFER
NUCLEAR FUELS
OPERATION
PERFORMANCE
SENSITIVITY ANALYSIS
STRESSES
THERMAL HYDRAULICS
WATER COOLED REACTORS
WATER MODERATED REACTORS
WATTS BAR-1 REACTOR