DOI QR코드

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EXPERIMENTAL AND ANALYTICAL STUDIES ON THE INSTABILITY IN THE LZCS FOR CANDU REACTORS

  • Ji, Joon-Suk (College of Advanced Technology Nuclear Eng., Kyunghee University) ;
  • Lee, Kwang-Ho (College of Advanced Technology Nuclear Eng., Kyunghee University) ;
  • Yun, Bum-Su (College of Advanced Technology Nuclear Eng., Kyunghee University) ;
  • Cha, Jung-Hun (College of Advanced Technology Nuclear Eng., Kyunghee University) ;
  • Kim, Sang-Nyung (College of Advanced Technology Nuclear Eng., Kyunghee University)
  • 발행 : 2008.12.31

초록

When reactivity insertion such as refueling occurs in CANDU reactors, the power and the water levels are tilted in the upper outer zone of the LZCS (Liquid Zone Control System) and fluctuate unstably for a certain period of time (1-5 days). The instability described above is observed in most CANDU reactors in service around the world, but its root cause is unidentified and no solutions to this problem have been established. Therefore, this study attempted to prove experimentally and analytically that the root cause lies in the hold-up of light water on the top of the TSP (Tube Support Plate) due to the mismatch between net volumetric flow rate of light water and helium crossing the narrowed porous TSP installed within the LZCS compartment. Our method was to perform a hydrodynamic simulation of in/outflow of light water and helium. Two solutions for the aforementioned instability of LZCS are suggested. One is to regulate the compartment for both inflowing helium gas and outflowing light water; the other is to enlarge the flow paths of helium and light water within TSP. The former may be applicable to nuclear reactors in service and the latter to those planned for construction.

키워드

참고문헌

  1. 'Unit 1 Shutdown Event from 05. Jan. 2001, Caused by LZC System Malfunction', CNE-PROD CERNAVODA
  2. 'Zone #1 Operating Data of Wolsong-2 (2003-11-21-22)',Korea Hydro and Nuclear Power(KHNP)
  3. 'Zone #13 Operating Data of Wolsong-2 (2002-10-30-31)',Korea Hydro and Nuclear Power(KHNP)
  4. 'Darlington NGS Unit 4Flux Tilt Events', COG/AECL CANDU Liquid Zone Control Workshop, Oct.30-31,2001
  5. 'LZC system instability of Wolsung-2', Korea Hydro and Nuclear Power(KHNP) Report, 1999
  6. 'CANDU 6 Liquid Zone Control Units', Atomic Energy of Canada Limited(AECL), Jan. 1995
  7. 'Wolsung-1 Nuclear Generating Station Liquid Zone Control System', Atomic Energy of Canada Limited(AECL), Sep. 1979
  8. 'Final Safety Analysis Report Wolsung Unit 2, 3 & 4', Korea Electric Power Corporation(KEPCO)
  9. 'Zone Control Assy. 2 Zone Assembly General Arrangement (XX-31751-2-1-GA-E)', Atomic Energy of Canada Limited(AECL)
  10. 'Reactivity Contrl Units. Zone Control Assy Baffle 2 (2Zone) (XX-31751-28-1-DD-C)', Atomic Energy of Canada Limited(AECL)
  11. 'CANDU 6 Generating Station Physisc Design Manual (86-03310-DM-000 Rev.1)', Atomic Energy of Canada Limited(AECL)
  12. B. Rouben, 'RFSP Program Description(TTR-370, Rev 1)', Atomic Energy of Canada Limited(AECL), 1995
  13. Lamarsh, John R., 'Introduction to NUCLEAR ENGINEERING', 1983
  14. James J. Duderstadt & Louis J. Hamilton, 'Nuclear Reactor Analysis', 1976
  15. Graham. B. Wallis, 'One-diminsional Two-phase Flow', 1969
  16. R. W. Fox, A. T. McDonald, 'Introduction to Fluid Mechanics', 1992
  17. D.A. jenkins, B. Rouben, 'Reactor Fuelling Simulation Program(RFSP) User's Manual', Atomic Energy of Canada Limited(AECL), 1993
  18. Richard Nicholls, 'COG Workshop on Liquid Zone Control System Gentilly 2 Experience', (October 30-31, 2001) 570