Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Numerical and analytical predictions of nuclear steam generator secondary side flow field during blowdown due to a feedwater line break

  • Jo, Jong Chull (Korea Institute of Nuclear Safety) ;
  • Jeong, Jae-Jun (Pusan National University, School of Mechanical Engineering) ;
  • Moody, Frederick J.
  • Received : 2020.05.21
  • Accepted : 2020.08.28
  • Published : 2021.03.25
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Abstract

For the structural integrity evaluation of pressurized water reactor (PWR) steam generator (SG) tubes subjected to transient hydraulic loading, determination of the tube-to-tube gap velocity and static pressure distributions along the tubes is prerequisite. This paper addresses both computational fluid dynamics (CFD) and analytical approaches for predicting the tube-to-tube gap velocity and static pressure distributions during blowdown following a feedwater line break (FWLB) accident at a PWR SG. First of all, a comparative study on CFD calculations of the transient velocity and pressure distributions in the SG secondary sides for two different models having 30 or no tubes is performed. The result shows that the velocities of sub-cooled water flowing between any adjacent two tubes of a tubed SG model during blowdown can be roughly estimated by applying the specified SG secondary side porosity to those of the no-tubed SG model. Secondly, simplified analytical approximate solutions for the steady two-dimensional SG secondary flow velocity and pressure distributions under a given discharge flowrate are derived using a line sink model. The simplified analytical solutions are validated by comparing them to the CFD calculations.

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References

  1. United States Nuclear Regulatory Commission, NUREG-0800, Standard Review Plan, "3.9.3 ASME CODE CLASS 1, 2, and 3 COMPONENT, SUPPORTS, and CORE SUPPORT STRUCTURES, USNRC, Washington, D. C., 2014.
  2. A. Ksinghal, G. Srikantiah, A review of thermal hydraulic analysis methodology for PWR steam generators and ATHOS3 code applications, Prog. Nucl. Energy 25 (1) (1991) 7-70. https://doi.org/10.1016/0149-1970(91)90041-M
  3. J.C. Jo, W.K. Shin, Fluidelastic instability analysis of operating nuclear steam generator U-tubes, NED 193 (1-2) (1999) 55-71.
  4. Y. Ferng, H. Chang, CFD investigating the impacts of changing operating conditions on the thermal-hydraulic characteristics in a steam generator, Appl. Therm. Eng. 28 (5-6) (2008) 414-422. https://doi.org/10.1016/j.applthermaleng.2007.05.014
  5. Y. Yang, B. Sun, L. Zheng, Computational fluid dynamics investigation of thermalehydraulic characteristics for a steam generator with and without tube support plates, Proc. IME C J. Mech. Eng. Sci. 227 (12) (2013) 2897-2911. https://doi.org/10.1177/0954406213479740
  6. T. Cong, W. Tian, G. Su, S. Qiu, Y. Xie, Y. Yao, Three-dimensional study on steady thermohydraulics characteristics in secondary side of steam generator, Prog. Nucl. Energy 70 (2014) 188-198. https://doi.org/10.1016/j.pnucene.2013.08.011
  7. Ansys Cfx User's Guide, ANSYS Inc., New York, 2019.
  8. J.C. Jo, J.J. Jeong, B.J. Yun, J. Kim, Numerical analysis of sub-cooled water flashing flow from a pressurized water reactor steam generator through an abruptly broken main feed water pipe, ASME JPVT 141 (2019) 1-10, 044501.
  9. F.R. Menter, Two equation eddy-viscosity turbulence models for engineering applications, AIAA J. 32 (8) (1994) 1598-1604. https://doi.org/10.2514/3.12149
  10. J.C. Jo, J.J. Jeong, B.J. Yun, Feedwater pipe break-induced hydraulic loads on nuclear steam generator tubes, Transactions of the ANS 121 (2019) 986-989, 2019 (Proc. American Nuclear Society 2019 winter meeting at Washington, D.C. on November 18, 2019).
  11. H.R. Vallentine, Applied Hydrodynamics, Butterworths, London, UK, 1959.
  12. R.D. Blevins, Applied Fluid Dynamics Handbook, Krieger, Malabar, FL, USA, 2003.
  13. D. Lasseux, F.J. Valdes-Parada, On the developments of Darcy 's Law to include inertial and slip effects, Compt. Rendus Mec. 345 (9) (2017) 660-669. https://doi.org/10.1016/j.crme.2017.06.005
  14. F.J. Moody, Introduction to Unsteady Thermofluid Mechanics, Wiley, NY, USA, 1990.