淺層水流完全發展流況之檢定

Calibration of the Fully Developed Flow for Shallow-Water Flows

陳昶憲(Chang-Shian Chen) ； 林昆志(Kun-Chih Lin) ； 王傳益(Chuan-Yi Wang)

《中華水土保持學報》 26卷3期 (1995/09) Pp. 159-165

https://doi.org/10.29417/JCSWC.199509_26(3).0001

摘要

本研究係對於不同床面粗糙度之流況，以三種檢定完全發展流況之經驗規範對6.4 m長之小型流槽進行檢驗，經由實測之速度剖面得知於20 mm水深、木板床面、A80號砂布床面及A24號砂布床面之完全發展長度均可於距入口3.1 m處產生。於水流通水斷面寬深比大於10之流況，以L = 240R之經驗式進行初步判斷較爲可行，然而對於二點以上之實測速度剖面資料進行比較是必需的。

關鍵字

完全發展流 ； 量測點

並列摘要

This study calibrated fully developed flow with three categories of rule of thumb by investigating shallow water flow in a small flume of 6.4m long with different bed roughness. A fully developed length of 3.1m measured from entrance has been observed from the velocity profiles that were measured from the flows of 20mm in depth over bed paved with wood plank, A80 sand cloth, or A24 sand cloth. The investigation reveals that it is feasible to make preliminary judgment by the empirical formula for L≥240R when the aspect ratio of flow is greater than 10; however, it is necessary to compare the velocity profiles measured from at least two sections for final conclusion.

並列關鍵字

Fully Developed Flow ； Measure Point