渐扩形渠道堰坝投潭水跃消能之比较研究.PDF

第十三屆海峽兩岸水利科技交流研討會，2009 年 11 月 23-24 日，台中市 漸擴形渠道堰壩投潭水躍消能之比較研究 1 1 1 2 廖苑雅 黃宏信 劉希羿 陳正炎 摘 要 本文研究旨在針對漸擴形渠道，因堰壩投潭作用後而產生水躍現象，依渠流之連續、能量及動 量方程式等解析，探討其水躍特性及消能功效，並與矩形、三角形渠道者分析比較。研究結果得共 軛水深比φ H 、相對能量損失E ΔE / i 及水躍消能效率η ，不但與水躍前福祿數Fi 、相對堰壩高 有 關，而且亦將受水躍前後渠道斷面寬度比 μ 影響，文中並建立漸擴形渠道之η( , η)μ H 公式，以 作為堰壩下游消能效率之估算或預測參考用。 A Study on Energy Dissipation of Hydraulic Jump in Gradually Expanding Channel Liao, Y. Y. 1, Huang, H. S. 1 , Liu, X. Y. 1, Chen, J. Y.2 Abstract The purpose of this study is to analyze the characteristics of a hydraulic jump in a gradually expanding channel. In this study, the rectangular section with the rectangle and triangle channel is conducted to investigate the characteristics behavior and energy dissipation of hydraulic jump under the free overfall flow in the weir. It was observed form the results that the conjugate depth ratio φ , relative energy lossE ΔE / i and energy dissipation efficiency η were not only influenced by the Froude number Fi and dimensionless height of weir H , but also by the channel width ratio μ . An approximate formula( η, η)μ H of the gradually expanding channel has been developed for calculations as well as prediction of the energy dissipation efficiency of the downstream in weir. 能最具成效且廣泛運用於消能設施上，能使上游 一、前言 之高動能量消減，而下游渠床不致有被掏刷沖蝕 台灣坡地面積廣大，為因地質、地形、氣象、 之顧慮。 水文及人為不當開發等因素影響，坡地災害頻 水躍（hydraulic j