交錯排列消能砥墩於渠道中水理現象之探討

Hydraulic Analysis of Staggered Arrangement of Stilling Baffle Pier in Channel

許可(Ke Hsu)

指導教授 ： 張德鑫

中原大學/工學院/土木工程研究所/碩士(2018年)

https://doi.org/10.6840/cycu201800527

摘要

本研究之預鑄混凝土模型採用交錯排列方式進行模型試驗，以求得其試驗模型之曼寧係數，並進而推估原型之曼寧係數值，其結果並與前期模型以規則排列方式下曼寧係數值做比較，探討是否能在節省成本下提高消能砥墩降低流速之成效。
根據實驗結果可知，當消能砥墩凸出高度最高且排列緊密時，其曼寧係數值為最大。於本實驗中當消能砥墩凸出高度5 cm及間距3 cm排列方式，曼寧係數值為最大，其曼寧n值也隨間距不同而有不同之結果。
從試驗對水深以及曼寧係數n值進行探討後得知，當水深和砥墩平均凸出高度之比值升高時，其曼寧係數值會漸趨於定值，即本試驗於此設計水深下有浸沒狀況發生，水深和砥墩平均凸出高度之比值與曼寧係數值呈現反比關係。當水深和砥墩平均凸出高度之比值大於6時，砥墩之消能作用已逐漸穩定，故本實驗結果可做為往後於渠流中設計消能砥墩之參考。

關鍵字

消能 ； 渠道 ； 水理現象

並列摘要

The concrete model of the concrete in this study was modeled by staggered arrangement. In order to obtain the Manning coefficient of the test model, and then to estimate the Manning coefficient value of the prototype. The result is compared with the Manning coefficient value of the previous model in a regular arrangement, discuss whether it is possible to improve the effectiveness of the energy dissipation loop to reduce the flow rate under cost saving.
According to the experimental results, when the height of the energy dissipation pier is the highest and the arrangement is tight, the Manning coefficient value is the largest. In this experiment, when the energy dissipation pier is 5 cm in height and 3 cm in pitch, the Manning coefficient is the largest. Its Manning n value also has different results depending on the spacing.
From the experiment, the water depth and the n value of the Manning coefficient are discussed. It is found that when the ratio of the water depth to the average height of the pier is increased, the Manning coefficient value will gradually become constant. That is, the immersion condition occurs in the water depth of this design. The ratio of the water depth to the average protruding height of the pier is inversely proportional to the Manning coefficient value. When the ratio of the water depth to the average protruding height of the pier is greater than 6, the energy dissipation effect of the pier is gradually stabilized. Therefore, the results of this experiment can be used as a reference for designing the energy dissipation pier in the channel.

並列關鍵字

Hydraulic Analysis ； Stilling Baffle Pier ； Channel

參考文獻

11. 陳麒升(2004)，「灌溉渠道生態工法水理研究」，私立中原大學土木工程研究所碩士論文。

12. 王繼緯(2005)，「回應曲面法應用於農業水路生態孔洞之設計」，私立中原大學土木工程研究所碩士論文。

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