| Summary: | 碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 98 === This study uses the upward-moving gate (full dam-break) and the collapse-type gate (partial dam-break) to observe dam-break flow under two different conditions. We collect and analyze previos literatures to design the upward-moving and collapse-type gate respectively. The results revel that the dam-break process, wave front velocity, and generation of mushroom jet are very different due to dam-break type.The mechanism of different dam-break flow will be examined and discussed in this paper.
The capacitancy wave gages and CCD camera were used to catch the front velocity and dam-break process.The experimental upstream water depth is kept at 30cm and 40cm for full dam-break conditions, and the ratio of downstream and upstream water depth is 0, 0.1, 0.2, and0.3. Zero value is dry-bed case. The collapse ratio for partial dam-break is 1 / 10, 1 / 5, 1 / 3. The filed of view of camera is 270cm long starting from the gat. From the experiments, the bore movement and the jet generation through down-stream are observed. Further, the position of mushroom jet was identified accurately, and the relationships among generation position, ratio of water depth, and maximum velocity were also obtained.
|
|---|
