Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical Analysis of Flow Distribution Inside a Fuel Assembly with Split-Type Mixing Vanes

분할 형태 혼합날개가 장착된 연료집합체 내부유동 분포 수치해석

  • Lee, Gong Hee (Nuclear Safety Research Department, Korea Institute of Nuclear Safety) ;
  • Cheong, Ae Ju (Nuclear Safety Research Department, Korea Institute of Nuclear Safety)
  • 이공희 (한국원자력안전기술원 원자력안전연구실) ;
  • 정애주 (한국원자력안전기술원 원자력안전연구실)
  • Received : 2015.12.10
  • Accepted : 2016.03.30
  • Published : 2016.05.01
Download PDF
⟨ Previous Next ⟩

Abstract

As a turbulence-enhancing device, a mixing vane, which is installed at a spacer grid of the fuel assembly, plays an important role in improving convective heat transfer by generating either swirl flow in the subchannels or cross flow between the fuel rod gaps. Therefore, both the geometric configuration and the arrangement pattern of a mixing vane are important factors in determining the performance of a mixing vane. In this study, in order to examine the flow-distribution features inside a $5{\times}5$ fuel assembly with split-type mixing vanes, which was used in the benchmark calculation of the OECD/NEA, we conduct simulations using the commercial computational fluid dynamics software, ANSYS CFX R.14. We compare the predicted results with measured data obtained from the MATiS-H (Measurement and Analysis of Turbulent Mixing in Subchannels-Horizontal) test facility. In addition, we discuss the effect of the split-type mixing vanes on the flow pattern inside the fuel assembly.

연료집합체의 지지격자에 설치된 혼합날개는 난류 강화 기구로서 부수로 내부에서 선회류 또는 연료봉 간극사이에서 횡류를 발생시켜 대류열전달을 증진시키는 역할을 한다. 따라서 혼합날개의 기하학적인 형상 및 배열 형태는 혼합날개의 성능을 결정하는 중요한 인자이다. 본 연구에서는 OECD/NEA의 벤치마크 계산에서 활용된 분할 형태의 혼합날개가 장착된 $5{\times}5$ 연료집합체 내부에서의 유동분포 특성을 파악하기 위해 상용 전산유체역학 소프트웨어인 ANSYS CFX R.14를 사용하여 계산을 수행하였고, 계산결과를 MATiS-H 시험장치의 측정값과 비교하였다. 또한 분할 형태의 혼합날개 형상이 연료집합체 내부유동 형태에 미치는 영향에 대해 설명하였다.

Keywords

References

  1. Chang S. -K., Kim, S. and Song, C. -H., 2014, "Turbulent Mixing in a Rod Bundle with Vaned Spacer Grids: OECD/NEA-KAERI CFD Benchmark Exercise Test," Nuclear Engineering and Design, Vol. 279, pp. 19-36. https://doi.org/10.1016/j.nucengdes.2014.05.013
  2. Lee, G. H., Bang, Y. S., Woo, S. W. and Cheong, A. J., 2014, "Numerical Study on the Effect of Reactor Internal Structure Geometry Treatment Method on the Prediction Accuracy for Scale-down APR+ Flow Distribution," Trans. Korean Soc. Mech. Eng. B, Vol. 38, No. 3, pp. 271-277. https://doi.org/10.3795/KSME-B.2014.38.3.271
  3. Lee, G. H., Bang, Y. S. and Cheong, A. J., 2015, "Numerical Analysis of the Effect of Hole Size Change in Lower-Support-Structure-Bottom Plate on the Reactor Core-Inlet Flow-Distribution," Trans. Korean Soc. Mech. Eng. B, Vol. 39, No. 11, pp. 905-911. https://doi.org/10.3795/KSME-B.2015.39.11.905
  4. Lee, G. H. and Cheong, A. J., 2015, "CFD Analysis for the Turbulent Flow Distribution in a Fuel Assembly with the Split-type Mixing Vanes by Using the Advanced Scale-Resolving Turbulence Models," Applied Mechanics and Materials, Vols. 752-753, pp. 902-907. https://doi.org/10.4028/www.scientific.net/AMM.752-753.902
  5. Lee, G. H. and Cheong, A. J., 2015, "Effect of the Accuracy Order of the Discretization Scheme on the Prediction Performance for the Turbulent Flow Structure inside Fuel Assembly: Sensitivity Study," Proc. of the ASME-JSME-KSME Joint Fluids Engineering Conference 2015, AJK2015-03027, July 26-31, SEOUL, KOREA.
  6. Lee, J. R., Kim, J. W. and Song, C. -H., 2014, "Synthesis of the Turbulent Mixing in a Rod Bundle with Vaned Spacer Grids Based on the OECD-KAERI CFD Benchmark Exercise," Nuclear Engineering and Design, Vol. 279, pp. 3-18. https://doi.org/10.1016/j.nucengdes.2014.03.008
  7. ANSYS CFX, Release 14.0, ANSYS Inc.
  8. Menter, F., 2001, "CFD Best Practice Guidelines for CFD Code Validation for Reactor Safety Applications," ECORA CONTRACT $N^{\circ}$ FIKS-CT-2001-00154.
  9. ANSYS CFX-Solver Modeling Guide, 2011, ANSYS Inc.