Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Development and validation of fuel stub motion model for the disrupted core of a sodium-cooled fast reactor

  • Kawada, Kenichi (Fast Reactor Cycle System Research and Development Center, Japan Atomic Energy Agency) ;
  • Suzuki, Tohru (Department of Nuclear Safety Engineering, Tokyo City University)
  • Received : 2021.05.19
  • Accepted : 2021.06.11
  • Published : 2021.12.25
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Abstract

To improve the capability of the SAS4A code, which simulates the initiating phase of core disruptive accidents for MOX-fueled Sodium-cooled Fast Reactors (SFRs), the authors have investigated in detail the physical phenomena under unprotected loss-of-flow (ULOF) conditions in a previous paper (Kawada and Suzuki, 2020) [1]. As the conclusion of the last article, fuel stub motion, in which the residual fuel pellets would move toward the core central region after fuel pin disruption, was identified as one of the key phenomena to be appropriately simulated for the initiating phase of ULOF. In the present paper, based on the analysis of the experimental data, the behaviors related to the stub motion were evaluated and quantified by the author from scratch. A simple model describing fuel stub motion, which was not modeled in the previous SAS4A code, was newly proposed. The applicability of the proposed model was validated through a series of analyses for the CABRI experiments, by which the stub motion would be represented with reasonable conservativeness for the reactivity evaluation of disrupted core.

Keywords

Acknowledgement

The authors express their sincere gratitude to Ms. Keiko Takahashi of NESI Inc. For technical assistance in parametric calculations using the SAS4A code and Mr. Kazuhiko Takahashi of NESI Inc. For technical support. The authors also would like to thank Dr. Yoshitaka Fukano of JAEA for his helpful comments.

References

  1. K. Kawada, T. Suzuki, Study on dominant aspects of unprotected loss-of-flow to be evaluated in the initiating phase for a sodium-cooled fast reactor, J. Nucl. Sci. Technol. (2020) 1-14.
  2. A.M. Tentner, F.E. Dunn, Kalimullah, K.J. Miles, Simulating unprotected accidents for advanced liquid metal reactors using the SAS4A accident analysis code, in: Conference of the Society of Computer Simulation, April 1988. Orlando, FL (USA).
  3. K. Kawada, I. Sato, Y. Tobita, W. Pfrang, L. Buffe, E. Dufour, Development of PIRT (phenomena identification and ranking table) for SAS-SFR (SAS4A) validation, July 7-11, in: 22nd International Conference on Nuclear Engineering, 2014. Prague, Czech Republic.
  4. K. Kawada, Y. Tobita, K. Takahashi, Preliminary result of validation study in SAS-SFR(SAS4A) code in simulated top and undercooled overpower conditions, December 14-18, in: 10th International Topical Meeting on Nuclear Thermal-Hydraulics, Operation and Safety (NUTHOS-10), 2014 (Okinawa, Japan).
  5. K. Kawada, T. Suzuki, Validation study in SAS4A code in simulated mild TOP condition, Transactions of the American Nuclear Society, ANS 2016 115 (6-10 November, 2016) 1597-1598.
  6. R.F. Cameron, F. Daguzan, W. Pfrang, I. Sato, Transient fuel pin behaviour up to failure in the CABRI-1 experiments, Int. Fast Reactor Safety Mtg. I (1990) 377.
  7. T. Suzuki, Y. Tobita, K. Kawada, H. Tagami, J. Sogabe, K. Matsuba, et al., A preliminary evaluation of unprotected loss-of-flow accident for a prototype fast-breeder reactor, Nuclear Engineering and Technology 47 (3) (April 2015) 240-252. https://doi.org/10.1016/j.net.2015.03.001
  8. T. Suzuki, K. Kamiyama, H. Yamano, S. Kubo, Y. Tobita, R. Nakai, et al., A scenario of core disruptive accident for Japan sodium-cooled fast reactor to achieve in-vessel Retention, J. Nucl. Sci. Technol. 51 (4) (2014) 493-513. https://doi.org/10.1080/00223131.2013.877405
  9. B.E. Boyack, G.E. Wilson, Lessons learned in obtaining efficient and sufficient applications of the PIRT process, Best Estimates (2004) 14-18. November 2004; Washington, DC (United States).
  10. T.G. Theofanous, C.R. Bell, An assessment of CRBR core disruptive accident energetics, April 21-25, in: Proc Int Topl Mtg Fast Reactor Safety, 1985 (Knoxville, Tennessee, USA).
  11. N. Nonaka, I. Sato, Improvement of evaluation method for initiating-phase energetics based on CABRI-1 in-pile experiments, Nucl. Technol. 98 (1) (1992) 54-69. https://doi.org/10.13182/NT92-A34650
  12. J. Charpenel, F. Lemoine, I. Sato, D. Struwe, W. Pfrang, Fuel pin behavior under the slow power ramp Ttransients in the CABRI-2 experiments, Nucl. Technol. 130 (3) (2000) 252-271. https://doi.org/10.13182/nt00-a3092
  13. I. Sato, F. Lemoine, D. Struwe, Transient fuel behavior and failure condition in the CABRI-2 experiments, Nucl. Technol. 145 (1) (2004) 115-137. https://doi.org/10.13182/nt04-a3464
  14. K. Baumung, K. Bohnel, H. Bluhm, The CABRI fast neutron hodoscope, Nucl. Technol. 71 (1) (1985) 353-365. https://doi.org/10.13182/NT85-A33732
  15. K. Baumung, G. Augier, Quantitative fuel motion determination with the CABRI fast neutron hodoscope: evaluation methods and results, Nucl. Technol. 96 (3) (1991) 302-313. https://doi.org/10.13182/NT91-A34591
  16. G. Kayser, J. Papin, The reactivity risk in fast reactors and the related international experimental programmes CABRI and SCARABEE, Global Environmental and Nuclear Energy Systems-2 32 (3) (1998) 631-638.