譚義績臺灣大學：生物環境系統工程學研究所陳昱升Chen, Yu-ShengYu-ShengChen2007-11-272018-06-292007-11-272018-06-292006http://ntur.lib.ntu.edu.tw//handle/246246/56123為了解魚窪地固床工內棲息空間的流場，因此將幾何邊界較複雜的魚窪地固床工，簡化成幾何邊界較簡單的多邊形模型，稱之為魚窪地固床工模型，並配合不同流況條件下，探討魚窪地固床工凹穴內漩渦流場。 本文主要應用質點影像測速儀(Particle Image Velocimetry, PIV )對一模擬魚窪地固床工之模型，於滑流與舌流流況條件下進行全域速度場之量測，在這之前，將魚窪地固床工試驗簡化成3/4孔穴流試驗，量測不同雷諾數下三維3/4孔穴流於中心對稱斷面上之二維速度場，並利用質點軌跡追蹤法將流場可視化。 模型則由透明壓克力板構成正立方體之孔穴，並於孔穴模型頂部設置傳輸皮帶構成五面為固定邊界及一面為移動邊界之封閉空間。研究中首先針對正立方體孔穴流進行雷諾數400、1000及2000之量測及流場可視化，並與前人之數值模擬結果比較，其目的為檢查模型製作是否符合要求及驗證PIV之操作與資料分析之正確性。再者修正正立方體孔穴模型為3/4孔穴流模型並於雷諾數由100至2000範圍中進行9組不同雷諾數之流場量測及分析；觀察3/4孔穴中於不同雷諾數時流場變化、漩渦結構之觀察、各漩渦之生成及其結構之幾何分析，以及當雷諾數持續增大時流場由穩態轉變非穩態時，其二維漩渦結構隨時間之震盪變化。最後探討魚窪地固床工考慮不同流況流況條件下（滑流與舌流），觀察垂直式跌水消能池與魚窪地固床工之流場特性與兩者相互之間流場比較。A cave at backside of vertical drop energy-dissipators is called fish refuge groundsills, which provide a shelter for fish as flood over this zone. This type cave often appears and drop flow scouring forms that. Simplified models are considered here and only flow field structures are emphasized and discussed. The flow field measurements in fish refuge groundsills are performed using Particle Image Velocimetry (PIV) in this thesis. There are three types of physical models are used for different purposes. To ensure the correctness of PIV operations and post-process analysis, the flow fields of cubic lid-driven cavity at Re = 400, 1000 and 2000 are first carried out and compare the velocity profiles along the horizontal and vertical center lines with benchmark by numerical simulations. The flow fields in 3/4 cavity from Re = 100 to 2000 are then executed. Two phenomena are observed in series of runs: 1) the several vortices appear with this cavity due to geometry and Reynolds number changing. 2) flow field becomes unsteady as Reynolds number more than 1200. The flow field in vertical drop energy-dissipators with and without cave under skimming and napped flow conditions are finally considered. Single inflow discharge is supplied, but the skimming and napped flow conditions are created by adjusting the distance between drop and sills. For skimming flow, the vortex in the pool driven by flow skimming stretch into the fish refuge groundsills and it then occupies all area of cavity but low velocity. The variations of the horizontal velocities at various locations within fish refuge groundsills are obscure. For another case, napped flow, a stronger clockwise vortex is generated due to tailwater attaching bottom. This vortex fully extends into the fish refuge groundsills, and variations of the horizontal velocities at various locations within fish refuge groundsills are obvious relative to skimming flow. Traditional drop flow is studied for consideration of energy dissipations. These series of measurements are first handled and preliminarily performed to start for the biological problems.中文摘要 I Abstract II 圖錄 VII 表錄 XVIII 第一章 緒論 1 1.1 研究背景 1 1.2 研究動機 1 1.3 文獻回顧 2 1.4 研究目的 4 第二章 試驗佈置與量測儀器 5 2.1 試驗設計 5 2.2 孔穴流驗證試驗 6 2.3 3/4孔穴流試驗 8 2.4 魚窪地固床工模型試驗 9 第三章 PIV 量測系統原理 12 3.1 PIV質點影像測速儀 12 3.1.1 高速質點顯像測速系統(HPIV System) 12 3.1.2 數位質點顯像測速系統( DPIV System ) 13 3.1.3 彩色質點影像測速法（CPIV） 13 3.1.4 大尺度質點影像量測法( LSPIV ) 14 3.2 PIV 量測系統 14 3.2.1 脈衝式雷射(pulsed laser) 14 3.2.2 CCD 電子耦合攝影機 (CCD Camera) 15 3.2.3 流場可視化追蹤質點( tracers ) 16 3.2.4 影像擷取處理介面( frame grabber ) 16 3.2.5 同步控制系統 ( Synchronizer ) 16 3.2.6 控制及分析軟體( Analysis subsystem ) 17 3.3 PIV流場可視化系統佈置 18 3.4 PIV 量測系統原理 20 3.5 PIV 試驗操作與設定 25 3.6 流場質點軌跡觀察法 29 第四章孔穴流模型試驗 30 4.1 孔穴流流場結構 30 4.2 孔穴流流場分析 32 4.3 孔穴流流速剖面分析 37 第五章 3/4孔穴流模型試驗 42 5.1 3/4孔穴流特性 42 5.2 3/4孔穴流穩定流場結構 43 5.3 3/4孔穴流穩定流場流速剖面解析 52 5.4 3/4孔穴流不穩定流場結構 69 5.5 3/4孔穴流不穩定流場流速剖面解析 87 第六章魚窪地固床工試驗 108 6.1 滑流與舌流流況特性探討 108 6.2 入流流況檢定 110 6.3 滑流流場結構之結果探討 112 6.4 舌流流場結構之結果探討 117 6.5 垂直式跌水消能池與魚窪地固床工流速剖面解析 124 第七章 結論與建議 147 7.1 結論 147 7.2 建議 148 參考文獻 150 符號說明 153 附錄 1549687386 bytesapplication/pdfen-US質點影像測速儀魚窪地固床工漩渦結構PIVfish refuge groundsillsvortexthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/56123/1/ntu-95-R93622040-1.pdf