Assessment of Existing Sierra/Fuego Capabilities Related to Grid-To-Rod-Fretting (GTRF)

Technical Report · Wed Jun 01 00:00:00 EDT 2011

DOI:https://doi.org/10.2172/1039399· OSTI ID:1039399

Rodriguez, Salvador B. ^[1]; Turner, Daniel Zack ^[1]

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1. Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

The following report presents an assessment of existing capabilities in Sierra/Fuego applied to modeling several aspects of grid-to-rod-fretting (GTRF) including: fluid dynamics, heat transfer, and fluid-structure interaction. We compare the results of a number of Fuego simulations with relevant sources in the literature to evaluate the accuracy, efficiency, and robustness of using Fuego to model the aforementioned aspects. Comparisons between flow domains that include the full fuel rod length vs. a subsection of the domain near the spacer show that tremendous efficiency gains can be obtained by truncating the domain without loss of accuracy. Thermal analysis reveals the extent to which heat transfer from the fuel rods to the coolant is improved by the swirling flow created by the mixing vanes. Lastly, coupled fluid-structure interaction analysis shows that the vibrational modes of the fuel rods filter out high frequency turbulent pressure fluctuations. In general, these results allude to interesting phenomena for which further investigation could be quite fruitful.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1039399
• Report Number(s): SAND--2012-0530
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
ACCURACY
COOLANTS
EFFICIENCY
FLUCTUATIONS
FLUID-STRUCTURE INTERACTIONS
FUEL RODS
HEAT TRANSFER
SIMULATION
SPACERS
THERMAL ANALYSIS
VANES