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研究生:施孟憲
研究生(外文):Mon-Shen Shi
論文名稱:潮流剖面特性之觀測與研究
論文名稱(外文):Observations of Tidal-Current Profiles
指導教授:曾若玄曾若玄引用關係
指導教授(外文):Ruo-Shan Tseng
學位類別:碩士
校院名稱:國立中山大學
系所名稱:海洋資源學系研究所
學門:自然科學學門
學類:海洋科學學類
論文種類:學術論文
論文出版年:2001
畢業學年度:90
語文別:中文
論文頁數:84
中文關鍵詞:邊界層南台灣剪應力應力淺海潮流對速層流速剖面
外文關鍵詞:taiwanfriction velocitytidal currentlog layerstressvelocity profilesroughness lengthdragboundary layer
相關次數:
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為了瞭解台灣南部淺海潮流剖面的特性以及接近海底底床邊界
層的結構,本研究是以一台底碇式的高頻ADCP錨碇於海底,做10 ~
20天的連續觀測,總共完成了六次實驗,其中第一次及第二次實驗地
點分別在高雄港內以及東港外海,後面四次實驗地點則都位於屏東後
灣海生館外海,其水深均介於12m ~ 18m。所測得的流速資料取20
分鐘平均之後,再利用對數分佈公式以4%精確度迴歸求得一條最佳
化直線,由其斜率與截距求得摩擦速度( u* )與粗糙長度( z0 )。由本研
究結果發現,(1)潮流剖面有隨流速的增加而有斜率越大的趨勢,(2)u*
有隨著實驗地點潮汐變化的趨勢,其中以東港外海u*比較大,最大可
達0.06m/s;(3)z0值相對比較散亂,但是在流速較大的東港外海大致
上也有呈現隨底層流速的遞增而減小的趨勢;(4)對數層的高度在流速
較大時高度較高;(5)曳力係數(CD)也有因實驗地點流速較大而值比較
小的趨勢;另外(6)降雨會造成濁度增加,進而使z0及CD也隨之增加。
而調和分析的結果也顯示,後灣在冬季期間,潮流橢圓主軸角度的垂
直變化很小,相位則是表層些微領先底層;在夏季期間,表層與底層
的主軸角度相差約15度且相位為底層領先約25度(約1.7小時),這
可能是因為後灣在夏季有些微層化現象所造成的。
This study aims to better understand the characteristics of the tidal- current profiles and the near-bed boundary layer structures off the southwestern coast of Taiwan. The velocity profile is measured by a bottom-mounted ADCP. Six experiments were conducted, each lasted 10~20 days and the water depth ranging 12~18 m. Twenty-minute averaged velocity profiles have been fitted to a logarithmic form with 4% accuracy. The friction velocity (u*) and roughness length (z0) are then derived from the slope and intercept of the best-fitted straight lines. Our results show that the profile shape and friction velocity vary tidally, the latter reaches O(0.06)ms-1 during peak current flow. The magnitude of z0 is large and scattered, but it shows a general trend of decrease with increasing flow speed. The observed log-layer height increases, and the bottom drag coefficient (CD) decrease, respectively with increasing flow speed. Measurements also show that water turbidity increases with rainfall, as a result the z0 and CD also increase. Finally, harmonic analysis of the tidal currents indicate significant changes between winter (homogeneous) and summer (stratified) conditions. In winter the vertical variation of orientation and phase is small, whereas in summer there was a 150 orientation and 250 phase difference (the bottom currents lead the surface currents) between the near surface and near bed regions.
目錄
章次 頁次
中文摘要………………….……………………………………...I
英文摘要………………….……………………………………...II
謝誌……………………….……………………………………...III
目錄………………………………………………………………IV
表目錄……………………………………………………………V
圖目錄……………………………………………………………VII
一、 前言…………………………………………………………1
二、 實驗地點及方法……………………………………………6
2.1 實驗地點與過程…………………………………...6
2.2 實驗儀器…………………………………………...8
2.3 分析方法…………………………………………...10
三、 研究結果……………………………………………………12
3.1 流速剖面的分類………………………………….12
3.2 流速剖面的分佈………………………………….13
3.3 摩擦速度 ( u* ) …………………………………..14
3.4 粗糙長度 ( z0 ) …………………………………..16
3.5 對數層高度……………………………………….18
3.6 底部拖曳係數 ( CD ) …………………………….18
3.7 調和分析與潮流橢圓…………………………….20
3.8 濁度變化………………………………………….21
四、 討論….……………………………………………………..23
4.1 潮汐對流速剖面之影響…………………………...23
4.2 流速的效應………………………………………...24
4.3 底質的效應………………………………………...27
4.4 降雨或濁度的效應………………………………...29
4.5 季節變化或層化的效應…………………………...29
五、 結論………………………………………………………..32
六、 參考文獻…………………………………………………..34
1. 黃煌煇等人 (1993):高雄海域海氣象調查研究。台南水工試驗所,
研究試驗報告第140號。
2. 曾若玄、孫佩君 (1997):近岸海潮流邊界層特性,第19屆海洋工
程研討會論文集,台中市,P. 381-385。
3. Anwar H.O. (1996):Velocity profile in shallow coastal waters, J.
Hydraulic Engineering, 122, 220-223.
4. Cheng R.T., Chi-Hai Ling and Gartner J.W. (1999):Estimates of
bottom roughness length and bottom shear stress in South San
Francisco Bay, California, J. Geophysical Research, 104, 7715-
7728.
5. Foreman M.G.G. (1977):Manual for Tidal Heights Analysis and
Prediction, Patricia Bay Pacific Mar. Sci. Rep. 77-10, Institute of
Ocean Sciences, Patricia Bay, Victoria, British Columbia, Canada,
97 pp.
6. Foreman M.G.G. (1978):Manual for Tidal Currents Analysis and
Prediction, Patricia Bay Pacific Mar. Sci. Rep. 78-6, Institute of
Ocean Sciences, Patricia Bay, Victoria, British Columbia, Canada,
70 pp.
7. Friedrichs C.T., Wright L.D., Hepworth D.A. and Kim S.C. (2000):
Bottom-boundary-layer processes associated with fine sediment
accumulation in coastal seas and bays, Continental Shelf Research,
20, 807-841.
8. Green M.O. and McCave I.N. (1995):Seabed drag coefficient under
tidal currents in the eastern Irish sea, J. Geophysical Research, 100,
16057-16069.
9. Gross T.F., Isley A.E. and Sherwood C.R. (1992):Estimation of
stress
and bed roughness during storms on the Nothern California Shelf,
Continental Shelf Research, 12, 389-413.
10.Howarth, M.J. (1998):The effect of stratification on tidal current
profiles, Continental Shelf Research, 18, 1235-1254.
11.Johnson, G. C., R. G. Lueck, and T. B. Sanford (1994):Stress on the
Mediterranean Outflow plume, 2, Turbulent dissipation and shear
measurements, J. Physical Oceanography, 24, 2084-2092.
12.Kawanisi, K. and S. Yokosi (1997):Characteristics of suspended
sediment and turbulence in a tidal boundary layer, Continental Shelf
Research, 17, 859-875.
13.Kundu P.K., Blanton J.O. and Janopaul M.M. (1981):Analysis of
current observations on the Georgia Shelf, J. Physical
Oceanography, 11, 1139-1149.
14.Lueck R.G. and Y. Lu (1997):The logarithmic layer in a tidal
channel, Continental Shelf Research, 17, 1785-1801.
15.Pingree, R. D. and D. K. Griffiths (1974):The turbulent boundary
layer
on the Continental Shelf, Nature, 250, 720-722.
16.Pond S. and Pickard G. L. (1983):Introductory Dynamical
Oceanography, Butterworth-Heinemann Ltd, Oxford, 2nd edition.
17.Sanford T.B. and Ren-Chieh Lien (1999):Turbulent properties in a
homogeneous tidal bottom boundary layer, J. Geophysical
Research, 104, 1245-1257.
18.Schauer U. (1987):Determination of bottom boundary layer
parameters at two shallow sea sites using the profile method,
Continental Shelf Research, 7, 1211-1230.
19.Schlichting, H. (1979):Boundary-Layer Theory, McGraw-Hill
Company, 817 PP.
20.Soulsby R.L. (1990):Tidal-current boundary layer, In:The Sea (ed.,
B.
Le Mehaute and D.M. Hanes), John Wiley and Sons, Inc., pp.523-
566.

21.Soulsby, R. L. and Dyer, K. R. (1981):The form of the near-bed
velocity profile in a tidally accelerating flow, J. Geophysical
Research, 86, 8067-8074
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