Title

水流墩前湧波之探討

Translated Titles

Bow wave and Hydraulic jump induced by cylindrical piers in open channel flows

Authors

劉力維

Key Words

超臨界流 ; 墩前湧波 ; 沖擊高度 ; 底床剪應力 ; 頻譜分析 ; Spectrum analysis. ; Bed shear stress ; Surge height ; Bow wave ; Supercritical Flow

PublicationName

中央大學土木工程學系學位論文

Volume or Term/Year and Month of Publication

2008年

Academic Degree Category

碩士

Advisor

周憲德;吳祚任

Content Language

繁體中文

Chinese Abstract

本文以實驗及數值計算分析超臨界流況下,橋墩受水流沖擊所造成的墩前湧波,探討橋墩尺度對振幅、頻率的影響;實驗於亞臨界流況下,利用超音波速度剖面儀(UVP)量測墩前速度場分佈,進一步探討墩前射流之分離位置及流場中頻率的特性,並透過數值模Truchas分析墩前射流位置及渦流分佈。實驗結果顯示,沖擊高度與上游福祿數呈正比之關係;UVP 能有效量測邊界層厚度及墩前渦流尺寸;透過數值模式,能進一步分析細部流場變化,如:渦度分佈、底床剪應力。本研究之結果可幫助於瞭解亞、超臨界流況中墩前沖擊高度與上游福祿數的關係,可供相關工程設計之參考。

English Abstract

Bow waves in front of cylindrical piers under different flow conditions, especially supercritical flows, are explored in this study by employing both flume experiments and 3D numerical simulation. An ultrasonic velocity profiler (UVP) is used to measure the downward/upward flow right in front of the pier, and the downward flow and the stagnation point along the profile are also measured. The magnitudes and the frequencies of bow waves are analyzed by image analysis. The vortex sizes are mainly determined by pier diameter alone. The dimensionless amplitude of bow waves is proportional to the square of upstream Froude numbers. The numerical simulations for piers in shallow water show that the shear stresses on the floor exhibit maximum value at the downstream sides, which is due to pier-induced surface drawdown and wake separation.

Topic Category 工學院 > 土木工程學系
工程學 > 土木與建築工程
Reference
  1. 2.胡富雁(2007) ,「波狀水躍流場之水理分析」,碩士論文,國立中央大學土木工程學系,中壢。
    連結:
  2. 6.Ahmed, F and Rajaratnam, N. (1998) “Flow around bridge piers” J. Hydraulic Engineering., vol.124, No.3, pp.288-300.
    連結:
  3. 8.Baker, C.J. (1979) “The Laminar Horseshoe Vortex”, J. Fluid Mech., Vol.95, pp.347-367.
    連結:
  4. 9.Ballio, F., Bettoni, C. and Frsnzetti, S. (1998) “ A Survey of Time-Averaged Characteristics of Laminar and Turbulent Horseshoe Vortices ,” J. Fluids Engineering, Vol.120, pp.233-242.
    連結:
  5. 10.Blevins., (1990) “Flow-Induce Vibration”, VAN NOSTRAND REINHOLD.
    連結:
  6. 11.Chorin, A. J.,(1968)“Numerical solution of the Navier-Stokes equations” Math. Comp., vol. 22, pp.745-762.
    連結:
  7. 12.Dargahi, B. (1989) “The Turbulent Flow Field around a Circular Cylinder” Experiment in Fluid 8., Vol.8, pp.1-12.
    連結:
  8. 13.Deardorff, J. W.,(1970)“A Numerical Study of Three-Dimensional Turbulent Channel Flow at Large Reynolds Number” J. Fluid Mech., vol. 41, NO. 2, pp.453-480.
    連結:
  9. 14.Graf, W.H. and Yulistiyanto, B. (1998) “ Experiments on flow around a cylinder;the velocity and vorticity fields ,” J. Hydraulic Research, Vol.36, No.4, pp.637-653.
    連結:
  10. 16.Harlow, F. H. and Welch, J. E. (1965) “Numerical Calculation of the Time-Dependent Viscous Incompressible Flow of Fluid with Free Surface”, Physics of Fluid, vol. 8, pp.2182–2189.
    連結:
  11. 17.Johnson, K. R. and Ting, C. K. (2003) ”Measurements of water surface profile and velocity field at a circular pier” J. Engineering mechanics., vol.129, No.5, pp.502-513.
    連結:
  12. 20.Lin, C., Lai, W.J. and Chang, K. A. (2003) “Simultaneous Particle Image Velocimetry and Laser Doppler Velocimetry Measurements of Periodical Oscillatory Horseshoe Vortex System near Square Cylinder-Base Plate Juncture” Dept. of Civil Engineering, National Chung-Hsing Univ., J. Hydraulic Engineering, pp.1173-1188.
    連結:
  13. 21.Liu, M., Rajaratnam, N. and Zhu, David Z. (2004) ”Turbulence Structure of Hydraulic Jumps of Low FroudeNumbers”, J. Hydraulic Engineering, Vol.130, No.6, pp.511-520.
    連結:
  14. 22.Muzzammil, M. and Gangadhariah, T. (2003) “The mean characteristics of horseshoe vortex at a cylinder pier ” J. Hydraulic Reach., Vol.3, pp.285-297.
    連結:
  15. 26.Wu, S., Rajaratnam, N. and Katopodis, C. (1998) “Oscillating Vertical Plane Turbulent Jet in Shallow Water”, Journal of Hydraulic Research, Vol.36, No.2, pp.229-234.
    連結:
  16. 1.吳益裕 (2007),「實用明渠水力學」,必中出版社,台中。
  17. 3.陳浩、高冬光(1991),「橋梁水力學」,人民交通出版社。
  18. 4.經濟部水利署(2002),量水設備技術規範草案。
  19. 5.謝奕生(2000),「流體體積法之應用於水躍分析」,碩士論文,私立淡江大學水資源及環境工程研究所,淡水。
  20. 7.Baker, C.J. (1978) “Vortex Flow Around the Base of Obstacles”, Ph.D. thesis, Univ of Cambridge, 123, pp. plus figure.
  21. 15.Henderson, F. M., (1966) ”Open channel flow” Macmillan Publishing co., pp.522.
  22. 18.Kubo, K.(1988)”Experiment Study on Horseshoe Vortex in the Upstream Front of Cylindrical Structure”, Modelling Soil-water-structure Interactions, Kolman et al., pp.117-126.
  23. 19.Lienhard, J. H. (1966) “Synopsis of Lift, Drag and Vortex Frequency Data for Rigid Circular Cylinders,” Washington State University, College of Engineering, Research Division Bulletin, pp.300.
  24. 23.Met-Flow SA, (2002) “UVP-DUO Monitor User’s Guide”, Switzerland,http://www.met-flow.com.
  25. 24.Rider, W. J. and Kothe, D. B.(1998)“Reconstructing Volume Tracking”Journal of Computational Physics, vol. 141, pp.112-152.
  26. 25.Schlichting, H. (1979) Boundary-Layer Theory, McGraw-Hill Company, Vol.160, pp.32.
  27. 27.Wu, T. R. (2004)” A Numerical study of three-dimensional breaking waves and turbulence effects” Ph.D. Dissertation, Dept. of Civil Engineering, Cornell University, pp.1-84.
Times Cited
  1. 林昱廷(2015)。孤立波通過結構物之數值模擬。逢甲大學水利工程與資源保育學系學位論文。2015。1-109。