DOI QR코드

DOI QR Code

Analysis of Compound Open Channel Flow Using Large Eddy Simulation (LES)

Large Eddy Simulation (LES)을 이용한 복단면 개수로 흐름 분석

  • Lee, Du Han (River Experiment Center, Korea Institute of Civil Engineering and Building Technology)
  • 이두한 (한국건설기술연구원 하천실험센터)
  • Received : 2017.02.14
  • Accepted : 2017.03.30
  • Published : 2017.03.31

Abstract

This study investigated compound open channel flow using OpenFOAM Large Eddy Simulation (LES). Large eddy simulations were carried out by solving the filtered continuity and momentum equations numerically. One equation LES and non-uniform grid were applied to capture the anisotropic turbulence and secondary flow near the wall. The results of large eddy simulations of turbulent flow in a compound open channel with deep and shallow flood plain depths are presented. These LESs are validated with experimental data, resulting in a good agreement between measured and calculated data. The role of anisotropic turbulence in generating secondary currents is illustrated.

본 연구는 OpenFOAM의 large eddy simulation (LES)를 이용하여 복단면 흐름을 분석하였다. LES는 여과된 연속방정식과 운동량 방정식을 수치적으로 해석하였다. 일방정식 LES와 비균일 격자를 적용하여 벽 부근의 난류 비등방성과 이차류를 재현하였다. 복단면 개수로 난류의 LES 결과는 홍수터의 수심이 깊은 경우와 얕은 경우에 대해서 제시하였다. 이들 결과는 실험 결과와 비교하였으며 실험결과와 계산 결과는 부합되는 양상을 보여준다. 또한 이차류를 생성하는 난류 비등방성의 역할에 대해서 제시하고 있다.

Keywords

References

  1. Ban, C. and Choi, S.U. 2011. Large eddy simulation of rectangular open-channel flow using OpenFOAM. Journal of the Korean Society of Civil Engineers 34(3): 833-840. https://doi.org/10.12652/Ksce.2014.34.3.0833
  2. Cater, J.E. and Williams, J.J.R. 2008. Large eddy simulation of a long asymmetric compound. Journal of Hydraulic Research 46(4): 445-453. https://doi.org/10.3826/jhr.2008.3134
  3. Constantinescu, G., Sukhodolov, A. and McCoy, A. 2009. Mass exchange in a shallow channel flow with a series of groynes: LES study and comparison with laboratory and fi eld experiments. Environmental Fluid Mechanics 9(6): 587. https://doi.org/10.1007/s10652-009-9155-2
  4. Kang, H. and Choi, S.-U. 2006a. Reynolds stress modelling of rectangular open-channel flow. Int. Journal for Numerical Methods in Fluids, 51, 1319-1334. https://doi.org/10.1002/fld.1157
  5. Kara, S., Stoesser, T., and Sturm, T.W. 2012. Turbulence statistics in compound channels with deep and shallow overbank flows. Journal of Hydraulic Research, 50(5): 482-493, DOI: 10.1080/00221686.2012.724194.
  6. Naot, D., Nezu, I. and Nakagawa, H. 1993. Hydrodynamic behavior of compound rectangular open channels. Journal of Hydraulic Engineering 119(3): 390-408. https://doi.org/10.1061/(ASCE)0733-9429(1993)119:3(390)
  7. OpenFOAM(R). 2011. The Open Source CFD Toolbox. Ver. 2.0.0. ESI Group, Paris, France.
  8. Pezzinga, G. 1994. Velocity distribution in compound channel flows by numerical modeling. Journal of Hydraulic Engineering 120(10): 1176-1198. https://doi.org/10.1061/(ASCE)0733-9429(1994)120:10(1176)
  9. Prinos, P., Townsend, R. and Tavoularis, S. 1985. Structure of turbulence in compound channel flows. Journal of Hydraulic Engineering 111(9): 1246-1261. https://doi.org/10.1061/(ASCE)0733-9429(1985)111:9(1246)
  10. Robertson, E., Choudhury, V., Bhushan, S. and Walters, D.K. 2015. Validation of OpenFOAM numerical methods and turbulence models for incompressible bluff body flows. Computer and Fluids 123: 122-145. https://doi.org/10.1016/j.compfluid.2015.09.010
  11. Rogallo, R.S. and Moin, P. 1984. Numerical simulation of turbulent flows. Annual Review of Fluid Mechanics 16(1): 99-137. https://doi.org/10.1146/annurev.fl.16.010184.000531
  12. Shiono, K. and Knight, D.W. 1991. Turbulent open channel flows with variable depth across the channel. Journal of Fluid Mechanics 222: 617-646. https://doi.org/10.1017/S0022112091001246
  13. Stoesser, T., Kim, S.J. and Diplas, P. 2010. Turbulent flow through idealized emergent vegetation. Journal of Hydraulic Engineering 136(12): 1003-1017. https://doi.org/10.1061/(ASCE)HY.1943-7900.0000153
  14. Thomas, T.G. and Williams, J.J.R. 1995. Large eddy simulation of turbulent flow in an asymmetric compound open channel. Journal of Hydraulic Research 33(1): 27-41. https://doi.org/10.1080/00221689509498682
  15. Tominaga, A. and Nezu, I. 1991. Turbulent structure in compound open-channel flows. Journal of Hydraulic Engineering 117(1): 21-41. https://doi.org/10.1061/(ASCE)0733-9429(1991)117:1(21)
  16. Van Balen, W., Blanckaert, K. and Uijttewaal, W.S.J. 2010. Analysis of the role of turbulence in curved open-channel flow at different water depths by means of experiments, LES and RANS. Journal of Turbulence 11(12), 1-34. https://doi.org/10.1080/14685241003627760

Cited by

  1. LES를 이용한 복단면 개수로의 바닥전단응력 분포특성 분석 vol.5, pp.4, 2018, https://doi.org/10.17820/eri.2018.5.4.199