Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/13883
標題: 垂直式單階跌水工與跌水消能池之流場特性探討
Study on the Characteristics of Vertical Drop Structure and Plunging Pool
作者: 邱泳仁
Jen, Chiu Yung
關鍵字: period;週期性;oscillation;plunging pool;振盪流;消能池
出版社: 土木工程學系
摘要: 
本實驗以實驗模型方式針對不同實驗條件下之單階跌水消能工,並以二維性流場作為探討範圍。藉由精密量測儀器之光纖雷射杜普勒測速儀及質點影像測速儀,進行非接觸式量測,並探討流場的特性;為了確實了解流體劇烈運動型態及渦流分布、消散增長之情形,使用高解析度之相機拍攝流場,其流場可視化相片作為定性觀察研究。文中對於單階跌水工與單階消能池之流場特性觀察與兩者相互之間比較、單階跌水工之水平速度剖面、單階消能池之週期性振盪流場及夾氣袋對於週期性震盪之影響,其相關特性變化均有所探討。

Free overfall could be seen in where a structure built across a natural and article channel to raise the level of water, with water flowing over it. This situation in which there is a sudden drop in the bed causing the flow to separate from the stream bed and move down the further step. Although many related topics were studied during last seventy years. However, many detailed flow structure including of the circulating vortex flow, the strong horizontal velocity profile, … etc, in the poor of free overfall are until see now. The purpose of the present study is make clear the velocity profile of free fall by the measuring result of particle image velocimetry (PIV) to compare with the measuring result of fiber laser Doppler velocimetry (FLDV). Further more, the study on the characteristics of periodic oscillation of free overfall with plunging pool make us to recognize that the situation of periodic oscillation occurring. Fiber laser Doppler velocimeter and wave gauge as well as aluminum-particle tracking visualization technique were employed, respectively, for quantitative measurements and qualitative observations. Main variables tested in the experiments include the oncoming (unit-width) discharge, the upstream and downstream heights of the plunging pool, and the lengths of the plunging pool and of the end sill. Moreover, the effect of air pocket, existing between the free overfall and upstream vertical wall of the drop structure, on the oscillation of plunging pool is also discussed in the present study. Some important features of the periodic oscillation in the plunging pool, including oscillation behaviour and non-dimensional oscillation frequency (i.e. Strauhal number), are briefly depicted.
URI: http://hdl.handle.net/11455/13883
Appears in Collections:土木工程學系所

Show full item record
 
TAIR Related Article

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.