Determining the minimum required uranium carbide content for HTGR UCO fuel kernels

Journal Article · Fri Mar 10 00:00:00 EST 2017 · Annals of Nuclear Energy (Oxford)

DOI:https://doi.org/10.1016/j.anucene.2017.02.023· OSTI ID:1360065

McMurray, Jacob W. ^[1]; Lindemer, Terrence B. ^[2]; Brown, Nicholas R. ^[3]; Reif, Tyler J. ^[4]; Morris, Robert N. ^[5]; Hunn, John D. ^[5]

---

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
2. MPi Business Solutions, Inc., Knoxville, TN (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division
4. X-Energy, LLC, Greenbelt, MD (United States)
5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fusion and Materials for Nuclear Systems Division

There are three important failure mechanisms that must be controlled in high-temperature gas-cooled reactor (HTGR) fuel for certain higher burnup applications are SiC layer rupture, SiC corrosion by CO, and coating compromise from kernel migration. All are related to high CO pressures stemming from free O generated when uranium present as UO₂ fissions and the O is not subsequently bound by other elements. Furthermore, in the HTGR UCO kernel design, CO buildup from excess O is controlled by the inclusion of additional uranium in the form of a carbide, UC_x. An approach for determining the minimum UC_x content to ensure negligible CO formation was developed and demonstrated using CALPHAD models and the Serpent 2 reactor physics and depletion analysis tool. Our results are intended to be more accurate than previous estimates by including more nuclear and chemical factors, in particular the effect of transmutation products on the oxygen distribution as the fuel kernel composition evolves with burnup.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE), Reactor Fleet and Advanced Reactor Development. Nuclear Reactor Technologies
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1360065
• Alternate ID(s): OSTI ID: 1415238
• Journal Information: Annals of Nuclear Energy (Oxford), Vol. 104, Issue C; ISSN 0306-4549
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
36 MATERIALS SCIENCE