頁籤選單縮合
題 名 | 明渠直角滙流之研究 |
---|---|
作 者 | 蔡長泰; 顏沛華; 徐碧治; | 書刊名 | 農業工程學報 |
卷 期 | 33:4 1987.12[民76.12] |
頁 次 | 頁1-16 |
分類號 | 443.1 |
關鍵詞 | 明渠; 直角; 匯流; |
語 文 | 中文(Chinese) |
中文摘要 | 明渠匯流為渠道系統或天然河系之局部現象。匯流時將發生水面超高、洩降等局部水力現象,也將造成匯流段上游之水面壅高,故有關渠道系統及河工設計等,應注意到匯流問題。 根據質量守恒、動量守恒及能量守恒原理,可推導出直角匯流段之基本方程式。基本方程式中有關匯流段長度、匯流能量損失係數及匯流段底床反作用力等,本研究進行104組水工實驗,分析出經驗公式。因此,亞臨界流況下,應用基本方程式,可由匯流段下游之水力條件求得匯流段上游之水深。另進行64組實驗以驗證導出之基本方程式及經驗公式,獲得良好之結果。 為方便計算,本研究另根據基本方程式中之動量方程式建立圖解法。由圖解法之曲線及實驗結果,可看出若匯流段下游福祿數小於0.3,則匯流流段上游水深與下游水深相差在5%以內。 |
英文摘要 | In many river engineering practices, such as building of a channel system, they usually involve design of a 90 degree junction. Due to flow complexities at this junction, such as the existences of head back, the longitudinal decent of water surface and transverse super elevation, etc., knowledge on how to describe these phenomena are often required. This paper suggests empirical formula for junction length, head loss and centrifugal force based on some experimental results. A set of governing equations for flow at the 90 degree junction is also given which is derive from conservative laws of mass, momentum an energy. These governing equations are further express graphically in assisting the computation such that the depth at a upstream reach of a 90 degree junction would be obtained from a downstream depth. |
本系統中英文摘要資訊取自各篇刊載內容。