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Development of Depth-averaged Mixing Length Turbulence Model and Assessment of Eddy Viscosity

수심평균 혼합거리 난류 모형의 개발 및 와점성계수의 평가

  • 최승용 (국립방재연구원) ;
  • 한건연 (경북대학교 공과대학 건축.토목공학부) ;
  • 황재홍 (한국수자원공사 경남1지구건설단)
  • Received : 2011.06.17
  • Accepted : 2011.09.22
  • Published : 2011.12.31

Abstract

The objective of this study is to develop an accurate and robust two-dimensional finite element method for turbulence simulation in open channels. The model is based on Streamline Upwind/Petrov-Galerkin finite element method and Boussinesq's eddy viscosity theory. The method developed in the study is depth-averaged mixing length model which assumes anisotropic and local equilibrium state of turbulence. The model calibration and validation were performed by comparing with analytical solutions and observed data. Several numerical simulations were carried out, which examined the performance of the turbulence model for the purpose of sensitivity analysis. The uniform channels that appear horizontal flow and vertical flow were carried out. The model was also applied to the Han river was in for the applicability test. The results were compared with the observed data. The suggested model displayed reasonable flow distribution compare to the observed data in natural river flow. As a result of this study, the two-dimensional finite element model provides a reliable results for flow distribution based on the turbulence simulation in open channels.

본 연구의 목적은 개수로에서 난류모의를 위한 2차원 모형을 개발하는데 있다. 연구모델은 Streamline Upwind / Petrov-Galerkin 유한요소법과 Boussinesq의 와점성이론을 기초로 하였는데, 수심적분을 취한 혼합거리 모형과 난류의 이방성과 국부평형의 조건을 적용하였다. 모형의 보정과 검증을 위해서 해석해와 관측자료를 활용하였다. 몇 가지 수치모의를 수행함으로써 난류모형의 민감도와 계산수행 능력을 확인할 수 있었다. 본 연구모형은 자연하천에서의 모형 적용성 확인을 위해서 한강유역에 적용하였고 모의치는 실측자료와 비교하였다. 개발된 모형은 자연하천에서의 관측자료와 비교적 잘 일치하는 것으로 나타났다. 결론적으로 본 연구의 2차원 유한요소모형은 개수로에서의 난류모의에 기초한 흐름분포에 있어 신뢰할만한 결과를 제공하는 것으로 나타났다.

Keywords

References

  1. 정영훈, 최성욱, 최정일. 2004. 저 레이놀즈 수개수로 난류흐름의 직접수치모의: 난류의 비등방성 해석. 2004년 한국수자원학회 학술대회논문집, pp. 376-380
  2. 최흥식. 1997. 난류모델을 이용한 개수로 급축소부 흐름의 수치해석. 한국수자원학회논문집 30(3): 201-210
  3. 강형식, 김규호 2009. 난류모형을 이용한 대응 식생수로 흐름수치모의. 2009 한국수자원학회 학술발표회 논문집. CD-ROM.
  4. Cea, L., Pena, L, Puertas, J, Vazquez-Cendon, M.E. and Pena, E. 2007. Application of several depth-averaged tuebulent models to simulate flow in vertical slot fishway. Journal of Hydraulic Engineering, 133(2):160-172. https://doi.org/10.1061/(ASCE)0733-9429(2007)133:2(160)
  5. Ewertowski. 2006. Automatic eddy viscosity assignment for 2-D hydrodynamics model. Publications of the Institue of Geophysics Polish Acaeny of Sciences. 9:124-131.
  6. King, I.P. and Norton, W.R 1978. Recent application of RMA's finite element models for two-dimensional hydrodynamics and water quality. Finite Element in Water Resources, Pentech Press pp. 281-299.
  7. Olsen, N.R.B. (2003). Three-dimensional CFD modeling of self-forming meandering channel. Journal of Hydraulic Engineering, 129(5): pp. 366-372. https://doi.org/10.1061/(ASCE)0733-9429(2003)129:5(366)
  8. Puertas, J., Pena, L. and Teijero, T.R. 2004. An experimental approach to the hydraulics of vertical slot fishway. Journal of Hydraulic Engineering, 130(1): 10-23. https://doi.org/10.1061/(ASCE)0733-9429(2004)130:1(10)
  9. Rameshwaran, P, and Naden, P.S. (2003). Three dimensional numerical simulation of compound channel flows. Journal of Hydraulic Engineering, 129(8): pp. 645-652. https://doi.org/10.1061/(ASCE)0733-9429(2003)129:8(645)
  10. Shumate, E.D. 1998. Experimental description of flow at an open channel junction. Master thesis, Univ. of Iowa, Iowa.
  11. Vazquez-Cendon, M.E. and Cea, L. 2007. High order upwind scheme for modeling turbulent shallow water flow in hydraulic structures. Proc. Appl. Math. Mech. 7(1) pp. 1100205-1100206. https://doi.org/10.1002/pamm.200700823
  12. Violeau, D., Bourban, S., Cheviet, C., Markofsky, M., Petersen, O., Roberts, W., Spearman, J., Toorman, E., Vested, H.J., and Weilbeer, H. (2002). Numerical simulation of cohesive sediment transport: Intercomparision of several numerical models. Proceedings in Marine Science, 5: pp. 75-89.
  13. Yulistiyanto B., 1998. Flow around a cylinder installed in a fixed-bed open channel. Ph. D. dissertation, Ecole Polytechnique federale, Lausanne, CH.