Thermal–hydraulic analysis of space nuclear reactor TOPAZ-II with modified RELAP5

  • Cheng-Long Wang
  • Tian-Cai Liu
  • Si-Miao Tang
  • Wen-Xi Tian
  • Sui-Zheng QiuEmail author
  • Guang-Hui Su


With the advantages of high reliability, power density, and long life, nuclear power reactors have become a promising option for space power. In this study, the Reactor Excursion and Leak Analysis Program 5 (RELAP5), with the implementation of sodium–potassium eutectic alloy (NaK-78) properties and heat transfer correlations, is adopted to analyze the thermal–hydraulic characteristics of the space nuclear reactor TOPAZ-II. A RELAP5 model including thermionic fuel elements (TFEs), reactor core, radiator, coolant loop, and volume accumulator is established. The temperature reactivity feedback effects of the fuel, TFE emitter, TFE collector, moderator, and reactivity insertion effects of the control drums and safety drums are considered. To benchmark the integrated TOPAZ-II system model, an electrical ground test of the fully integrated TOPAZ-II system, the V-71 unit, is simulated and analyzed. The calculated coolant temperature and system pressure are in acceptable agreement with the experimental data for the maximum relative errors of 8 and 10%, respectively. The detailed thermal–hydraulic characteristics of TOPAZ-II are then simulated and analyzed at the steady state. The calculation results agree well with the design values. The current work provides a solid foundation for space reactor design and transient analysis in the future.


Space nuclear reactor TOPAZ-II Thermal–hydraulic analysis RELAP5 modification 


  1. 1.
    L.S. Mason, A comparison of Brayton and Stirling space nuclear power systems for power levels from 1 kilowatt to 10 megawatts. AIP Conf. Proc. 552(1), 1017 (2001). MathSciNetCrossRefGoogle Scholar
  2. 2.
    G.L. Bennett, R.J. Hemler, A. Schock, Space nuclear power: an overview. J. Propul. Power 12(5), 901 (1996). CrossRefGoogle Scholar
  3. 3.
    D. Buden, Summary of space nuclear reactor power systems (1983–1992). Idaho National Engineering Laboratory Report (1993), Report ID: INEL/MISC-93085.
  4. 4.
    A.J. Glassman, Summary of Brayton cycle analytical studies for space-power system applications. Sol. Energy. 7 (1964).
  5. 5.
    R.S Dabrowski, US-Russian Cooperation in science and technology: A case study of the TOPAZ space-based nuclear reactor international program. Connect. Q. J. 13(1), 71 (2013).
  6. 6.
    S.S. Voss, E.A. Rodriguez, Russian TOPAZ II system test program (1970–1989). AIP Conf. Proc. 301(1), 803 (1994). CrossRefGoogle Scholar
  7. 7.
    J.F. Fairchild, J.P. Koonmen, F.V. Thome, Thermionic system evaluated test (TSET) facility description. AIP Conf. Proc. 246(1), 836 (1992). CrossRefGoogle Scholar
  8. 8.
    V.P. Nicitin, B.G. Ogloblin, A.N. Luppov et al., Special features and results of the ‘‘TOPAZ II’’ nuclear power system tests with electric heating. AIP Conf. Proc. 246(1), 41 (1992). CrossRefGoogle Scholar
  9. 9.
    M.S. El-Genk, H. Xue, C. Murray et al., TITAM thermionic integrated transient analysis model: load-following of a single-cell TFE. AIP Conf. Proc. 246(1), 1013 (1992). CrossRefGoogle Scholar
  10. 10.
    M.S. El-Genk, D.V. Paramonov, A.C. Marshall, Startup simulation of the TOPAZ-II Reactor system for accident conditions. AIP Conf. Proc. 301(1), 1059 (1994). CrossRefGoogle Scholar
  11. 11.
    M.S. El-Genk, H. Xue, D.V. Paramonov, Start-up simulation of a thermionic space nuclear reactor system. AIP Conf. Proc. 271(2), 935 (1993). CrossRefGoogle Scholar
  12. 12.
    S.S. Voss, The TOPAZ II space reactor response under accident conditions. Presented at the International Topical Meeting on the Safety of Advanced Reactors, Pittsburgh, PA, 18–20 Apr. 1994.
  13. 13.
    V.H. Standley, D.B. Morris, M.J. Schuller, CENTAR modeling of the TOPAZ-II: loss of vacuum chamber cooling during full power ground test. AIP Conf. Proc. 246(1), 1129 (1992). CrossRefGoogle Scholar
  14. 14.
    W.W. Zhang, Z.Y. Ma, D.L. Zhang et al., Transient thermal–hydraulic analysis of a space thermionic reactor. Ann. Nucl. Energy 89, 38 (2016). CrossRefGoogle Scholar
  15. 15.
    W.W. Zhang, D.L. Zhang, W.X. Tian et al., Thermal-hydraulic analysis of the improved TOPAZ-II power system using a heat pipe radiator. Nucl. Eng. Des. 307, 218 (2016). CrossRefGoogle Scholar
  16. 16.
    S.S. Voss, TOPAZ-II system description, in Proceedings of the Fourth International Conference on Engineering, Construction, and Operations in Space, Albuquerque, NM. 717 (1994).
  17. 17.
    C.B. Jackson, Liquid metals handbook. Sodium-NaK Supplement. Atomic Energy Commission, Washington, DC; Bureau of Ships, Report ID: TID-5277 (1955).
  18. 18.
    Z.Y. Qian, Thermal Properties of Low Melting Point Metals (Science Press, China, 1985). In Chinese Google Scholar
  19. 19.
    O.J. Foust, Sodium-NaK engineering handbook (Gordon & Breach Science Pub, New York, 1972)Google Scholar
  20. 20.
    M. Zemansky, R. Dittman, Heat and Thermodynamics (McGraww-Hill Inc Pub, New York, 1997)Google Scholar
  21. 21.
    S. Aoki, O.E. Dwyer, Current liquid-metal heat transfer research in Japan. Tokyo Inst. of Tech., Report ID: NSA-29-000316. 1973.
  22. 22.
    O.E. Dwyer, P.S. Tu, Bilateral heat transfer to liquid metals flowing turbulently through annuli. Nucl. Sci. Eng. 21(1), 90 (1965). CrossRefGoogle Scholar
  23. 23.
    N.E. Todreas, M.S. Kazimi, Nuclear systems: thermal hydraulic fundamentals (CRC Press, Boca Raton, 2012), p. 306Google Scholar
  24. 24.
    D.V. Paramonov, M.S. El-Genk, Comparison of a TOPAZ-II Model with experimental data from the V-71 unit tests. AIP Conf. Proc. 301(1), 829 (1994). CrossRefGoogle Scholar

Copyright information

© China Science Publishing & Media Ltd. (Science Press), Shanghai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society and Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Cheng-Long Wang
    • 1
  • Tian-Cai Liu
    • 2
  • Si-Miao Tang
    • 1
  • Wen-Xi Tian
    • 1
  • Sui-Zheng Qiu
    • 1
    Email author
  • Guang-Hui Su
    • 1
  1. 1.Department of Nuclear Science and TechnologyXi’an Jiaotong UniversityXi’anChina
  2. 2.China Institute of Atomic EnergyBeijingChina

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