DOI QR코드

DOI QR Code

Experiment investigation on flow characteristics of open natural circulation system

  • 투고 : 2021.08.24
  • 심사 : 2021.11.13
  • 발행 : 2022.05.25

초록

Experimental research on flow characteristics of open natural circulation system was performed, to figure out the mechanism of the open natural circulation behaviors. The influence factors, such as the heating power, the inlet subcooled and the level of cooling tank on the flow characteristics of the system were examined. It was shown that within the scope of the experimental conditions, there are five flow types: single-phase stable flow, flash and geyser coexisting unstable flow, flash stable flow, flash unstable flow, and flash and boiling coexisting unstable flow. The geyser flow in flash and geyser coexisting unstable flow is different from classic geysers flow. The flow oscillation period and amplitude of the former are more regular, is a newly discovered flow pattern. By drawing the flow instability boundary diagram and sorting out the flow types, it is found that the two-phase unstable flow is mainly characterized by boiling and flash, which determine the behavior of open natural circulation respectively or jointly. Moreover, compared with full liquid level system, non-full liquid level system is more prone to boiling phenomenon, and the range of heat flux density and undercooling degree corresponding to unstable flow is larger.

키워드

과제정보

This work is financed by China Nuclear Power Technology Research Institute Co., Ltd. The authors would like to express their appreciation to this.

참고문헌

  1. Taek Sun, Lim, et al., Experimental Investigation of Two-phase Natural Circulation Loop as Passive Containment Cooling System, Nuclear Engineering and Technology, 2021.
  2. J.A. Boure, A.E. Bergles, L.S. Tong, Review of two-phase flow instability, Nucl. Eng. Des. 25 (2) (1973) 165-192. https://doi.org/10.1016/0029-5493(73)90043-5
  3. K.C. Jain, M. Petrick, D. Miller, S.G. Bankoff, Self-sustained hydrodynamic oscillations in a natural-circulation boiling water loop, Nucl. Eng. Des. 4 (3) (1966) 233-252. https://doi.org/10.1016/0029-5493(66)90049-5
  4. M. Aritomi, J.H. Chiang, T. Nakahashi, et al., Fundamental study on thermo-hydraulics during startup in natural circulation boiling water reactor (I): thermo-hydraulic instabilities, J. Nucl. Sci. Technol. 29 (7) (1992) 631-641. https://doi.org/10.1080/18811248.1992.9731576
  5. J.H. Chiang, M. Aritomi, M. Mori, Fundamental study on thermo-hydraulics during start-up in natural circulation boiling water reactors (II):Natural circulation induced by hydrostatic head fluction, J. Nucl. Sci. Technol. 30 (3) (1993) 203-211. https://doi.org/10.1080/18811248.1993.9734471
  6. H. Chiang, M. Aritomi, M. Mori, Fundamental study on thermo-hydraulics during start-up in natural circulation boiling water reactors (III):Effects of system pressure on geysering and natural circulation oscillation, J. Nucl. Sci. Technol. 31 (9) (1994) 883-893. https://doi.org/10.1080/18811248.1994.9735239
  7. S.K. Yang, Stability of flashing-driven natural circulation in a passive moderator cooling system for Canadian SCWR, Nucl. Eng. Des. 276 (3) (2014) 259-276. https://doi.org/10.1016/j.nucengdes.2014.06.009
  8. X. Yan, G. Fan, Z. Sun, Study on flow characteristics in an open two-phase natural circulation loop, Annals of Nuclear 104 (2017) 291-300. https://doi.org/10.1016/j.anucene.2016.12.038
  9. Kyung Mo Kim, Dae Hyung Lee, Cheol 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 (2020) 147.
  10. Xiaofan Hou, Zhongning Sun, Guangming Fan, et al., Experimental and analytical investigation on the flow characteristics in an open natural circulation system, Appl. Therm. Eng 124 (2017) 673-687. https://doi.org/10.1016/j.applthermaleng.2017.05.201
  11. S.Y. Jiang, D. Emendorfer, Subcooled boiling and void flashing in a natural circulation system at heating reactor conditions, Kerntechnik 58 (5) (1993) 62-67. https://doi.org/10.1515/kern-1993-580122
  12. K. Fukuda, T. Kobori, Classification of two-phase flow instability by density wave oscillation model, J. Nucl. Sci. Technol. 16 (2) (1979) 95-108. https://doi.org/10.1080/18811248.1979.9730878
  13. A. Manera, H. Tim, J.J. van der Hagen, Stability of natural-circulation-cooled boiling water reactors during startup: experimental Results, Nucl. Technol. 143 (1) (2003) 77-88. https://doi.org/10.13182/nt03-a3399