Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/10170
標題: 光滑渠槽明渠流通過透水四面體框架之紊流特性研究
Turbulence characteristics of flows passing through tetrahedron frames in a smooth open-channel
作者: 張天峰
Chang, Tien-Feng
關鍵字: 光纖雷射杜普勒流速儀;fiber-optic laser Doppler velocimeter ( FLDV );明渠流;透水框架;總剪應力;阻力係數;open channel;tetrahedron frame;total stress;drag coefficient
出版社: 土木工程學系所
引用: 1.台灣省水利局,防洪工程設計手冊,1969。 2.何淑君,「透水框架群應用於固床工下游沖刷保護之研究」,碩士論文,國立中興大學土木工程研究所,2009。 3.吳龍華、周春天、嚴忠民、王南海,架空率桿件長寬比對四面六邊透水框架群減速促淤效果的影響,水利水運工程學報,第3期,第74~77頁,2003。 4.林呈,跨河構造物防制沖刷之技術與策略研究(應用剛性或柔性攔砂堰作為橋基保護方法之評估探討),行政院公共工程委員會專案研究計畫,1999。 5.周根娣、顧正華、高柱、唐洪武,四面六邊透水框架尾流場水力特性,長江科學院院報,第22期,第3卷,第9-12頁,2005。 6.唐洪武及肖洋等人,透水框架式四面體水流結構及阻力特性研究,第五屆全國泥沙基本理論學術討論會,2002。 7.洪健豪,「三維光滑明渠紊流流場之量測與模擬」,博士論文,國立中興大學土木工程研究所,2003。 8.張文捷等人,四面六邊透水框架群用於長江護岸固腳工程實例及設計要點,江西水利科技,第28卷,第1期,2002。 9.張志源,「單槽洗衣機之液體平衡環數值模擬」,碩士論文,國立中央大學機械工程研究所,2011。 10.黃怡仁,「直排筐網群樁於渠道中之沖淤現象」,碩士論文,國立成功大學水利及海洋工程研究所,2009。 11.郭耀麒、張耀澤,柔性固床工之破壞機制與保護方式水槽試驗案例研究,經濟部水利署,水利,第16期,第201-210頁,2006。 12.劉彩吉,「應用大渦紊流模擬 (LES) 模式於二維與三維之通道內紊流流場及其熱傳研究」,碩士論文,國立成功大學造船暨船舶機械工程研究所,2002。 13.盧昭堯、賴進松、林詠彬等人,河道固床工破壞機制與減沖促淤新工法研擬 (2/2),經濟部水利署水利規劃試驗所,2009。 14.Bagnold, R.A. (1996). “Approach to the sediment transport problem from general physics.” United States government printing office, geological survey professional paper 422-I. 15.Carollo, F.G., Ferro. V., and Termini, D. (2002). “Flow velocity measurements in vegetated channels.” J. Hydraul. Eng., 128(7), 664-673. 16.Khan, I.M., Simons, R.R., and Grass A.J. (2005). “Effect on turbulence production due to sudden change in flow regimes.” J. Hydraul. Res., 43(5), 549-555. 17.Mignot, M., and Cienfuegos, R. (2010). “Energy dissipation and turbulent production in weak hydraulic jumps.” J. Hydraul. Eng., 136(2), 116-121. 18.Nezu, I. and Rodi, W (1986). “Open-channel flow measurements with a laser Doppler anemometer.” J. Hydraul. Eng., 112(5), 333-355. 19.Nezu, I. and Nakagawa, H. (1993). “Turbulent structures and bursting phenomena over roughness discontinuity in open channel flows.” turbulent structures and related environment in various water flows, Scientific Research Activities, 122-129. 20.Nezu, I. and Nakagawa, H. (1993). “Turbulent in open-channel flows.”, Kyoto University ( in Japan ). 21.Pao, H. F. (1967). “Fluid dynamics.” Charles E. Merrill books, Inc. Columbus, Ohio. 22.Smagorinsky, J. (1963). “General circulation experiments with the primitive equations.” Monthly Weather Review, 91(3), 99-164. 23.Temple, D. M. (1986). “Velocity distribution coefficients for grass-lined channels.” J. Hydraul. Eng., 113(2), 193-205. 24.Wu, F.C., Shen, H.W. and Chou, Y.J. (1999). “Variation of roughness coefficients for unsubmerged and submerged vegetation.” J. Hydraul. Eng., 125(9), 934-942. 25.Young, D.F., Munson B.R. and Okiishi T.H. (2001). “A brief introduction to fluid mechanics – 2nd ed.” John Wiley & Sons, USA. 26.http://hippo.bse.ntu.edu.tw/~wenlian/waterchang/wchang-5.htm 27.http://photo.xuite.net/lifeforrent/1264459/47.jpg 28.http://big5.xinhuanet.com/gate/big5/news.xinhuanet.com/world/2007-05/13/content_6092385.htm 29.http://dongthanh.myweb.hinet.net/A-E1.htm 30.http://big5.china.com.cn/chinese/2002/Nov/231832.htm 31.http://met.fzu.edu.cn/cai/sg/sgpics/index.asp 32.http://www.chisui-net.co.jp/block/sankaku.htm 33.http://www.yankodesign.com/2009/08/17/heavenly-abode/
摘要: 
台灣地勢陡峭,颱洪時期水流湍急,經常造成河床沖刷劇烈與水工結構物破壞。近年來四面體框架於水利工程設計之應用頗多,其特點為減速促淤,在拋投區可達到減少沖刷之效果。惟目前文獻中,關於四面體框架如何消能,及其水力特性與減沖促淤機制則有待更深入之研究。
本研究首先利用二維光纖雷射杜普勒流速儀 ( 2D-FLDV ),於光滑明渠流中量測水流通過單一四面體框架附近流場。除利用量測資料探討基本物理機制外,亦針對浸沒流場進行模式率定與驗證。量測資料顯示,四面體具有遲滯流速、擾動水流增加耗能與減小底床處總剪應力之功效。經修正Carollo等人 (2002) 明渠流通過水生植物之流速分佈理論,吾人可快速求出鄰近透水四面體框架下游處之流速剖面,並獲得合理模擬成果。此外,本研究配合 ANSYS CFX 11套裝軟體,可以LES模式初步模擬出單顆四面體附近之流場特性。
其次,量測多排數四面體群,除基本物理機制外,亦探討排數效應對流場之影響。實驗結果顯示,緩坡與陡坡條件下物理機制差異頗大,緩坡條件下僅需較少排數其減阻效應即可達極限值,而陡坡條件下排數效應影響較為顯著。此外,根據浸沒流場下之實驗量測資料,本研究提出減速率與阻力係數之相關迴歸式,藉此吾人可快速推估水流通過四面體群框架後之相關物理特性參數。

Due to the steep topography, rivers in Taiwan usually carry rapid flows during typhoon seasons, which frequently cause severe riverbed deformations and hydraulic structure failures. Recently the use of tetrahedron frames in the hydraulic engineering design has an increasing trend. The main characteristics of these tetrahedron frames include generation of turbulence, retardation of the flows and inducing sediment deposition near the structures. However, basic research related to the investigation of the physical mechanism of the related phenomena is still limited.
First, a two-dimensional fiber-optic laser Doppler velocimeter ( 2D-FLDV ) was adopted to measure the flow field near a tetrahedron frame in a smooth boundary open channel. The experimental data were used not only to clarify the physical mechanism of the flow retardation caused by the tetrahedron frame, but also to calibrate the simple velocity-profile model under the submerged flow conditions. The experimental results revealed that the tetrahedron frame can reduce the mean longitudinal flow velocity, boundary shear stress, and increase the turbulence intensities. With proper modifications of Carollo et al.’s (2002) theory for channel flows passing through vegetation, the velocity profiles immediately downstream of the tetrahedron frame can be quickly predicted with reasonable accuracy. Moreover, the flow field near a single tetrahedron can be approximately predicted by the LES model in ANSYS CFX 11 software package.
As to the tetrahedron frame group tests, the experimental data were used to clarify the physical mechanism and the effect of row number on the flow. The experimental results indicated that only few rows of tetrahedron frames are needed for the deceleration rate to reach a limit under a mild slope condition. Conversely, the effect of row number is sensitive for a steep slope condition. Furthermore, the multiple regressions of deceleration rate and drag coefficient have been performed using the measured data. The developed empirical equations can be applied to predict the physical parameters for the flows passing through the tetrahedron frames.
URI: http://hdl.handle.net/11455/10170
其他識別: U0005-2307201216361600
Appears in Collections:土木工程學系所

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