Transactions of the Korean Society of Pressure Vessels and Piping (한국압력기기공학회 논문집)

Korean Society of Pressure Vessels and Piping (한국압력기기공학회)
권호 표지
DOI QR코드

DOI QR Code

Evaluation of MCCI Behaviors in the Calandria Vault of CANDU-6 Plants Using CORQUENCH Code

CORQUENCH 코드를 활용한 중수로 calandria vault에서의 MCCI 거동 분석

  • Received : 2021.11.01
  • Accepted : 2021.12.22
  • Published : 2021.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Molten corium-concrete interaction (MCCI) is one of the most important phenomena that can lead to the potential hazard of late containment failure due to basemat penetration during a severe accident. In this study, MCCI analytical models of the CORQUENCH code were prepared through verification calculations of several experiments, which had been performed using concrete types similar to those of the calandria vault floor in CANDU-6 plants. The behaviors of thermal-hydraulic variables related to MCCI phenomena were analyzed under the conditions of dry floor and water flooding during the severe accident stemming from a hypothetic station blackout. Uncertainty analyses on the ablation depth were also carried out. It was estimated that the concrete ablation was not interrupted due to the continuous MCCI process under the dry condition but was terminated within 24 hours under the water flooding condition. It was confirmed that the water flooding as a mitigating action was effective to achieve the quenching and thermal stabilization of the melt discharged from the calandria vessel, showing that the present models are capable of reasonably simulating MCCI phenomena in CANDU-6 plants. This study is expected to provide the technical bases to the accident management strategy during the late-phase severe accidents.

Keywords

Acknowledgement

본 연구는 원자력안전위원회의 재원으로 한국원자력안전재단의 지원을 받아 수행한 원자력안전연구사업의 연구결과입니다. (No. 1805003)

References

  1. Sevon, T., 2005. Molten Core Concrete Interactions in Nuclear Accidents - Theory and Design of an Experimental Facility. VTT Tiedotteita. Research Notes 2311.
  2. Thompson, D.H., Flink, J.K., Armstrong, D.R., Spencer, B.W., Sehgal, B.R., 1992, "Thermal hydraulic aspects of the large-scale integral MCCI test in the ACE program," 2nd OECD/NEA CSNI Specialist Meeting on Molten Core Debris-Concrete Interactions, NEA/CSNI/R(92)10, Karlsruhe, Germany, April 1-3.
  3. Copus, E.R., Blose, R.E., Brockmann, J.E., Simpson, R.B., Lucero, D.A., 1990, "Core-concrete interactions using molten UO2 with zirconium on basaltic basemat: the SURC-2 experiment," U.S. Nuclear Regulatory Commission, Washington DC, NUREG/CR-5564.
  4. Copus, E.R., 1992, "Sustained Uranium Dioxide/Concrete Interaction Tests: The SURC Test Series," 2nd OECD/NEA CSNI Specialist Meeting on Molten Core Debris-Concrete Interactions, Nuclear Energy Agency, Paris, NEA/CSNI/R(92)10, Karlsruhe, Germany, April 1-3.
  5. Farmer, M.T., Spencer, B.W., Binder, J.L., Hill, D.J., 2001, "Status and Future Direction of the Melt Attack and Coolability Experiments (MACE) Program at Argonne National Laboratory," Proceedings 9th Int. Conference on Nuclear Engineering (ICONE-9), Nice, France, April 8-12.
  6. Farmer, M.T., Lomperski, S., Basu, S., 2004, "Results of Reactor Material Experiments Investigating 2-D Core-Concrete Interactions and Debris Coolability," Proceedings ICAPP04, Pittsburgh, PA USA, June 13-17.
  7. Farmer, M.T., Lomperski, S., Kilsdonk, D., Aeschlimann, B.W., Basu, S., 2007, "A summary of Findings from the Melt Coolability and Concrete Interaction (MCCI) Program," Proceedings ICAPP07, Nice, France, May 13-18.
  8. Journeau, C.et al., 2009, "Two-dimensional interaction of oxidic corium with concretes: The VULCANO VB test series," ANN NUCL ENERGY, 361597-1613. https://doi.org/10.1016/j.anucene.2009.07.006
  9. Bradley, D.R., Gardner, D.R., Brockmann, J.E., Griffith, R.O., 1993, "CORCON-Mod3: An Integrated Computer Model for Analysis of Molten Core-Concrete Interactions," U.S. Nuclear Regulatory Commission, Washington DC, NUREG/CR-5843.
  10. Fauske & Associates, Inc., 1994, "MAAP4: Modular Accident Analysis Program for LWR, Power Plant User Manual," EPRI Project RP3131-02.
  11. Cranga, M., Fabianelli, R., Jacq, F., Barrachin, M., Duval, F., 2005, "The MEDICIS code, a versatile tool for MCCI modelling," Proceedings of ICAPP05, Seoul, Korea, May 15-19.
  12. Park, S.Y., Ahn, K.I., Song, Y.M., 2015, "Uncertainty Analysis of the Potential Hazard of MCCI during Severe Accidents for the CANDU6 Plant," SCI TECHNOL NUCL INS, http://dx.doi.org/10.1155/2015/462941.
  13. Nie, M., Fischer, M., Lohnert, G., 2002, "Advanced MCCI modeling based on stringent coupling of thermal hydraulics and real solution thermochemistry in COSACO," Proceedings of 10th Int. Conference on Nuclear Engineering (ICONE-10), Arlington, Virginia USA, April 14-18.
  14. Spindler, B., Tourniaire, T., Seiler, J.M., 2006, "Simulation of MCCI with the TOLBIAC-ICB code based on the phase segregation model," NUCL ENG DES, 2362264-2270. https://doi.org/10.1016/j.nucengdes.2006.03.023
  15. Farmer, M.T., 2010, "The CORQUENCH Code for Modeling of Ex-Vessel Corium Coolability under Top Flooding Conditions, Code Manual-Version 3.03," OECD/MCCI-2010-TR03.
  16. Cranga, M., et al., 2010, "Simulation of corium concrete interaction in 2D geometry," PROG NUCL ENEG, 5276-83.
  17. Corradini, M.L., 1983, "A Transient Model for the Ablation and Decomposition to Concrete," NUCL TECHNOL, 62, 263-273.
  18. Brockmann, J.E.,Arellano, F.E.,Lucero, D.A., 1989, "Validation of Models of Gas Holdup in the CORCON Code," U.S. Nuclear Regulatory Commission, Washington DC, NUREG/CR-5433.
  19. Lomperski, S., Farmer, M.T., 2006a, "Experimental Evaluation of the Water Ingression Mechanism for Corium Cooling," NUCL ENG DES, 237, 905-917. https://doi.org/10.1016/j.nucengdes.2006.12.009
  20. Lomperski, S., Farmer, M.T., Basu, S., 2006b, "Experimental Investigation of Corium Quenching at Elevated Pressure," NUCL ENG DES, 236, 2271-2280. https://doi.org/10.1016/j.nucengdes.2006.03.041
  21. Ricou, F.B., Spalding, D.B., 1961, "Measurements of Entrainment of Axisymmetrical Turbulent Jets," J FLUID MECH, 11, 21-32. https://doi.org/10.1017/S0022112061000834
  22. Lomperski, S., Farmer, M.T., 2009, "Corium Crust Strength Measurements," NUCL ENG DES, 238, 2551-2561. https://doi.org/10.1016/j.nucengdes.2009.06.013
  23. Ishii, M., Zuber, N., 1979, "Drag Coefficient and Relative Velocity in Bubbly, Droplet, or Particle Flows," AICHE J, 25, 843-855. https://doi.org/10.1002/aic.690250513
  24. Yu, S.O., Cho, M.K., Lee, K.W., Baek, K.L., 2020, "Code Analysis of Effect of PHTS Pump Sealing leakage during Station Blackout at PHWR Plants," Trans. of the KPVP, Vol. 16, No. 1, pp. 11-21. http://dx.doi.org/10.20466/KPVP.2020.16.1.011
  25. Robb. K., Francis M., Farmer M., 2014, "Ex-Vessel Core Melt Modeling Comparison between MELTSPREAD-CORQUENCH and MELCOR 2.1," ORNL/TM-2014/1.
  26. Wilk, S.S., 1941, "Determination of sample sizes for setting tolerance limits," The Annals of Mathematical Statistics, 12, 91-96. https://doi.org/10.1214/aoms/1177731788
  27. Hong, I.S., Oh, D.Y., Kim, I.G., 2013, "Generic Application of Wilks' Tolerance Limit Evaluation Approach to Nuclear Safety," OECD/CSNI Workshop on Best Estimate Methods and Uncertainty Evaluations, NEA/CSNI/R(2013)8, Barcelona, Spain, November 16-18.
  28. Lim, H.G., Han, S.H., 2009, "Development of T/H uncertainty analysis S/W MOSAIQUE." Proceedings of the 10th Korea-Japan Joint Workshop on PSA (KJPSA '09), May 18-20.