Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
권호 표지
DOI QR코드

DOI QR Code

Thermal-hydraulic phenomena and heat removal performance of a passive containment cooling system according to exit loss coefficient

  • Sun Taek Lim (Department of Mechanical Engineering, Incheon National University) ;
  • Koung Moon Kim (Korea Institute of Fusion Energy) ;
  • Jun-young Kang (Thermal hydraulic and severe accident safety research division, Korea Atomic Energy Research Institute) ;
  • Taewan Kim (Department of Safety Engineering, Incheon National University) ;
  • Dong-Wook Jerng (School of Energy System Engineering, Chung-Ang University) ;
  • Ho Seon Ahn (Department of Mechanical Engineering, Incheon National University)
  • Received : 2024.02.20
  • Accepted : 2024.05.13
  • Published : 2024.10.25
Download PDF
⟨ Previous Next ⟩

Abstract

The natural circulation system has been widely studied for use in various applications because of its inherent advantage. However, it has a key weakness called flow instability that makes the system unstable. Through massive previous research, the mechanisms of flow instability were analyzed, but there was an ambiguous aspect related to the effect of experimental parameters on the phenomenon. Particularly, there has been no report on the heat transfer performance of the system when flow instability phenomena were present. In this study, thermal-hydraulic phenomena of a two-phase natural circulation system that functions as a passive containment cooling system (PCCS) was investigated according to experimental parameters, namely, the temperature boundary (120-158 ℃) and exit loss coefficient (0-34.5) under atmospheric pressure conditions. The experimental results showed five different flow types in the loop. The flow modes that occurred by the interaction between flashing and boiling were classified by referring to the mass flow rate, void fraction, and visualization data. The system was more unstable when the temperature boundary conditions increased, but it was more stable when the exit loss coefficient increased. These results have only been confirmed in our research. The reason for the results is that the flow conditions are located on the boundary between Density Wave Oscillation I and the stable flow region, and that boundary does not have clear criteria. In addition, comparing the heat transfer performance of a system by heat rate can confirm the effect of flow instability on the thermal performance of the passive cooling system. As a result, the high exit loss coefficient stabilizes the system better than the low case and has similar heat removal performance.

Keywords

Acknowledgement

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (Ministry of Science and ICT) (NRF-2017M2B2B1072553).

References

  1. W. He, Y. Zhang, J. Ji, Comparative experiment study on photovoltaic and thermal solar system under natural circulation of water, Appl. Therm. Eng. 31 (16) (2011) 3369-3376.
  2. W. He, T.-T. Chow, J. Ji, J. Lu, G. Pei, L.-s. Chan, Hybrid photovoltaic and thermal solar-collector designed for natural circulation of water, Appl. Energy 83 (3) (2006) 199-210.
  3. T. Van der Hagen, A. Stekelenburg, The low-power low-pressure flow resonance in a natural circulation cooled boiling water reactor, Nucl. Eng. Des. 177 (1-3) (1997) 229-238.
  4. C.P. Marcel, M. Rohde, T. Van Der Hagen, An experimental parametric study on natural circulation BWRs stability, Nucl. Eng. Des. 318 (2017) 135-146.
  5. S. Arneth, J. Stichlmair, Characteristics of thermosiphon reboilers, Int. J. Therm. Sci. 40 (4) (2001) 385-391.
  6. J. Luitjens, Q. Wu, S. Greenwood, M. Corradini, Mechanistic CHF modeling for natural circulation applications in SMR, Nucl. Eng. Des. 310 (2016) 604-611.
  7. S. Wang, Y.-C. Lin, G. Wang, M. Ishii, Experimental investigation on flashing-induced flow instability in a natural circulation scaled-down test facility, Ann. Nucl. Energy 171 (2022) 109023.
  8. M. Kawakubo, M. Aritomi, H. Kikura, T. Komeno, An experimental study on the cooling characteristics of passive containment cooling systems, Journal of nuclear science and technology 46 (4) (2009) 339-345.
  9. J. Boure, A. Bergles, L.S. Tong, Review of two-phase flow instability, Nucl. Eng. Des. 25 (2) (1973) 165-192.
  10. S. Kakac, B. Bon, A review of two-phase flow dynamic instabilities in tube boiling systems, Int. J. Heat Mass Tran. 51 (3-4) (2008) 399-433.
  11. S. Jiang, M. Yao, J. Bo, S. Wu, Experimental simulation study on start-up of the 5 MW nuclear heating reactor, Nucl. Eng. Des. 158 (1) (1995) 111-123.
  12. M. Aritomi, J.H. Chiang, T. Nakahashi, M. Wataru, M. Mori, Fundamental study on thermo-hydraulics during start-up in natural circulation boiling water reactors,(I) thermo-hydraulic instabilities, J. Nucl. Sci. Technol. 29 (7) (1992) 631-641.
  13. M. Furuya, F. Inada, T. Van der Hagen, Flashing-induced density wave oscillations in a natural circulation BWR-mechanism of instability and stability map, Nucl. Eng. Des. 235 (15) (2005) 1557-1569.
  14. S.-K. Yang, Stability of flashing-driven natural circulation in a passive moderator cooling system for Canadian SCWR, Nucl. Eng. Des. 276 (2014) 259-276.
  15. H. Liu, N. Todreas, M. Driscoll, An experimental investigation of a passive cooling unit for nuclear plant containment, Nucl. Eng. Des. 199 (3) (2000) 243-255.
  16. X. Hou, Z. Sun, G. Fan, J. Tang, J. Su, Flow characteristics in an open two-phase natural circulation loop, in: International Conference on Nuclear Engineering, American Society of Mechanical Engineers, 2014. V02BT09A004.
  17. X. Hou, Z. Sun, J. Su, G. Fan, An investigation on flashing instability induced water hammer in an open natural circulation system, Prog. Nucl. Energy 93 (2016) 418-430.
  18. X. Hou, Z. Sun, G. Fan, L. Wang, Experimental and analytical investigation on the flow characteristics in an open natural circulation system, Appl. Therm. Eng. 124 (2017) 673-687.
  19. X. Hou, J. Qiu, Z. Sun, S. Yao, C. He, X. Yang, S. Wang, Y. Yang, A study on the steady-state flow behavior of the flashing-driven open natural circulation system, Appl. Therm. Eng. 182 (2021) 115903.
  20. J. Bang, D.-W. Jerng, H. Kim, Comparisons of performance and operation characteristics for closed-and open-loop passive containment cooling system design, Nucl. Eng. Technol. 53 (8) (2021) 2499-2508.
  21. K.M. Kim, D.H. Lee, I.C. Bang, Analysis of natural circulation behaviors and flow instabilities of passive containment cooling system design for advanced PWR using MARS-KS code, Int. J. Heat Mass Tran. 147 (2020) 118982.
  22. S.T. Lim, K.M. Kim, H. Kim, D.-W. Jerng, H.S. Ahn, Experimental investigation of two-phase natural circulation loop as passive containment cooling system, Nucl. Eng. Technol. 53 (12) (2021) 3918-3929.
  23. D.W. Green, M.Z. Southard, Perry's Chemical Engineers' Handbook, McGraw-Hill Education, 2019.
  24. E.W. Lemmon, R.T. Jacobsen, S.G. Penoncello, D.G. Friend, Thermodynamic properties of air and mixtures of nitrogen, argon, and oxygen from 60 to 2000 K at pressures to 2000 MPa, J. Phys. Chem. Ref. Data 29 (3) (2000) 331-385.
  25. K. Woo, Experimental and Analytical Study of Stability Characteristics of Natural Circulation Boiling Water Reactors during Startup Transient, Purdue University, 2008.
  26. F.-S. Wang, L.-W. Hu, C. Pan, Thermal and stability analysis of a two-phase natural circulation loop, Nucl. Sci. Eng. 117 (1) (1994) 33-46.
  27. K. Cheng, T. Meng, C. Tian, H. Yuan, S. Tan, Experimental investigation on flow characteristics of pressure drop oscillations in a closed natural circulation loop, Int. J. Heat Mass Tran. 122 (2018) 1162-1171.
  28. I.S. Kyung, S.Y. Lee, Experimental observations on flow characteristics in an open two-phase natural circulation loop, Nucl. Eng. Des. 150 (1) (1994) 163-176.