DOI QR코드

DOI QR Code

Focusing effect of a Metallic Layer according to the Cooling Condition and Height in a Severe Accident

중대사고시 금속용융물층의 냉각 조건과 높이가 열속 집중 현상에 미치는 영향

Moon, Je-Young;Chung, Bum-Jin
문제영;정범진

  • Received : 2015.02.02
  • Accepted : 2015.03.12
  • Published : 2015.03.31

Abstract

Focusing effect of a metallic layer in a severe accident depending on the aspect ratios and cooling conditions of top plate and side wall was investigated. Experiments were carried out for Rayleigh numbers and aspect ratio in the range of $8.49{\times}10^7{\sim}5.43{\times}10^9$, 0.135~0.541 respectively. In order to achieve high Rayleigh numbers, the heat transfer experiments were replaced by mass transfer experiments based on the heat and mass transfer analogy. A sulfuric acid-copper sulfate ($H_2SO4-CuSO_4$) electroplating system was adopted as the mass transfer system. The experimental results agreed well with the Rayleigh-Benard natural convection correlations of Dropkin and Somerscales and Globe and Dropkin. When compared with the standard Rayleigh-Benard problem, the cooling by the side wall is even higher than the top. For a shorter height, the interaction between the heated and cooled plumes increases due to decrease of the height. Thus, the heat transfer increases.

Keywords

Focusing effect;Severe accident;Core melt;Analogy concept;Electroplating system

References

  1. R.J. Park et al., Evaluation of In-Vessel Corium Retention under a Severe Accident, Korea Atomic Energy Research Institute, 2008, KAERI/TR-3537/2008
  2. J.H. Song et al., Strategy for the Development of Severe Accident Analysis Technology, 2009, Korea Atomic Energy Research Institute, KAERI/AR-834/2009
  3. J.L. Rempe et al., In-Vessel Retention Strategy for High Power Reactors, 2005, Idaho National Engineering and Environmental Laboratory, INEEL/EXT04-02561
  4. T. G. Theofanous et al., In-vessel coolability and retention of a core melt, Nuclear Engineering and Design, 1997, 169, 1-48 https://doi.org/10.1016/S0029-5493(97)00009-5
  5. F. P. Incropera and D. P. Dewitt, Fundamentals of Heat and Mass Transfer, 1990, WILEY, New York
  6. Adrian Bejan, Convection Heat Transfer : 3rd Edition, 1948, 275-277
  7. F. Heslot et al., Transitions to turbulence in helium gas, Phys. Rev., 1987, 36, 5870-5873 https://doi.org/10.1103/PhysRevA.36.5870
  8. T. Y. Chu, R. J. Goldstein, Turbulent convection in a horizontal layer of water, J. Fluid Mech., 1973, 60, 141-159 https://doi.org/10.1017/S0022112073000091
  9. R. J. Goldstein et al., High-Rayleigh-number convection in a horizontal enclosure, J. Fluid Mech., 1990, 213, 111-126 https://doi.org/10.1017/S0022112090002245
  10. D. Dropkin, E. Somerscales, Heat Transfer by natural convection in liquids confined by two parallel plates which are inclined at various angles with respect to the horizontal, Trans. ASME C: J. Fluid Mech., 1965, 23, 337-353
  11. S. Globe, D. Dropkin, Natural convection heat transfer in liquids confined by two horizontal plates and heated from below, Trans. ASME, 1959, 81, 24-28
  12. Liu and Theofanous, In-vessel coolability and retention of a core melt, 1996, 1, Appendix N
  13. Massimo Corcione, Effects of the thermal boundary conditions at the sidewalls upon natural convection in rectangular enclosures heated from below and cooled from above, International Journal of Thermal Sciences, 2003, 42, 199-208 https://doi.org/10.1016/S1290-0729(02)00019-4
  14. Levich, V. G., Physicochemical Hydro-dynamics, Prentice-Hall, Englewood Cliffs, N. J., 1962
  15. Selman, J. R. and Tobias, C. W., Mass Transfer Measurement b the Limiting Current Technique, Advances in Chemical Engineering, ELSEVIER, 1978, 10, 211-318 https://doi.org/10.1016/S0065-2377(08)60134-9
  16. E. J. Fenech, C. W. Tobias, Mass Transfer by Free Convection at Horizontal Electrodes, Electrochimica Acta, 1960, 2, 311-325 https://doi.org/10.1016/0013-4686(60)80027-8
  17. Ko, S. H., Moon, K. W. and Chung, B. J., Applications of Electroplating Method for Heat Transfer Studies Using Analogy Concept, Nuclear Engineering and Technology, 2006, 38, 251-258
  18. Heo, J. H. and Chung, B. J., Visualization of Natural convection Heat Transfer on a Horizontal Cylinder using the Copper Electroplating System, Trans. of the KSME(B), 2011, 35, 43-51
  19. Kang, K. U. and Chung, B. J., The Effects of the Anode size and Position on the Limiting Currents of Natural Convection Mass Transfer Experiment in a Vertical Pipe, Trans. of the KSME (B), 2010, 34, 1-8
  20. Fenech, E. J. and Tobias, C. W., Mass transfer by free convection at horizontal electrode, Electrochimica Acta, 1960, 2, 311-325 https://doi.org/10.1016/0013-4686(60)80027-8

Acknowledgement

Supported by : 한국연구재단(NRF)