Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
권호 표지
DOI QR코드

DOI QR Code

Determination of burnup limit for CANDU 6 fuel using Monte-Carlo method

  • Received : 2020.04.10
  • Accepted : 2020.07.23
  • Published : 2021.03.25
Download PDF
⟨ Previous Next ⟩

Abstract

KHNP recently has obtained the approval for the commercialization of the modified 37-element (or 37 M) fuel bundle and now is loading the 37 M fuel bundles in CANDU-6 reactors in KOREA. One of the main issues for approval was the burnup limit. Due to CANDU design and neutronic characteristics, there was no specific burnup restriction of a fuel bundle. The absence of a burnup limit does not mean that a fuel bundle can stay in the CANDU reactor without a time limit. However, the regulator requested traditional design values as well as the burnup limit reflecting the computer code uncertainty. The method for the PWR burnup limit was not applied to the CANDU fuel bundle. Since there was no approved methodology to build the burnup limit with uncertainties, KHNP introduced a Monte-Carlo method coupled with a 95/95 approach to determine the conservative burnup limit from the viewpoint of the centerline temperature, internal pressure, strain measurement deviation. Moreover, to consider the uncertainties of various computing models, a converted power uncertainty was introduced. This paper presents the methodology and puts forward the limits on burnup, evaluated for each of the existing and modified fuel bundles, in consideration of the pressure tube aging condition.

Keywords

References

  1. Wm J. Garland, The Essential CANDU, A Textbook on the CANDU Nuclear Power Plant Technology, University Network of Excellence in Nuclear Engineering (UNENE), ISBN 0-9730040. Retrieved from https://www.unene.ca/education/candu-textbook.on.2020.01.15, p 1585.
  2. M.R. Floyd, Extended-burnup CANDU Fuel Performance, the 7th International Conference on CANDU Fuel, Sep. 2001. CNS, Kingston, Ontario, Canada.
  3. M. Tayal, ELESTRES: performance of nuclear fuel, circumferential ridging, and multiaxial elastic-plastic stresses in sheath, in: International Conference on CANDU Fuel, Oct. 1986. Chalk River, Canada.
  4. G.G. Chassie, ELESTRES-IST 1.2: User's Manual, 153-113370-UM-001 Rev.0, AECL, Oct. 2006.
  5. W.W.R. Inch, J.H. Lau, P.D. Thompson, P.J. Reid, Increasing CANDU operating margins with CANFLEX fuel, in: COG/IAEA 6th Tech. Comm. Meeting on the Exchange of Operational Safety Experience of PHWR, Sep. 2000. Quebec.
  6. P.G. Lucuta, Hj Matzke, I.J. Hastings, A pragmatic approach to modeling thermal conductivity of irradiated UO 2 fuel: review and recommendations, J. Nucl. Mater. 232 (1996) pp166-pp180. https://doi.org/10.1016/S0022-3115(96)00404-7
  7. G.G. Chassie, ELESTRES-IST 1.2: Validation Manual, 153-113370-SVM-001 Rev.0, AECL, Nov. 2006.
  8. P. Schwanke, RFSP-IST Version REL_3-04: Users' Manual, 153-117360-UM-002, Dec. 2006.

Cited by

  1. Risk Assessment Models to Improve Environmental Safety in the Field of the Economy and Organization of Construction: A Case Study of Russia vol.13, pp.24, 2021, https://doi.org/10.3390/su132413539