Studies on Applying Spiral Flow Type Channel to Develop Spiliways

管道通常建在坡度大于1/5的区域。然而，在管道的施工过程中，会出现一些问题，如管道初始部分被浮木或沙子堵塞、水流溢出、管道坍塌等。这是非常。堵塞难以清除。基于这些原因，本研究开发了一种明渠结构，该结构可以在坡度为1/1或河道曲线角为90度的区域建造。这种流量控制方法是一种新发展起来的技术。通过将矩形通道改造成圆形壁面通道，可以将高速电流向上流动的能量转化为螺旋流动的能量，使电流流动顺畅。在坡度陡峭、沟道或溜槽弯曲的山区建设螺旋流型沟道结构系统，使螺旋流型沟道结构技术的应用成为可能。该方法适用于狭窄位置的溢洪道，以及水坝或水库的弯曲溢洪道。目前，该新型溢洪道已在某一地区投入使用。当溢洪道堰宽与圆弧断面沟道宽度相同时，水流易于控制；但当堰宽等于或大于河道宽度时，就会引起溢流。因此，今后计划开展将溢洪道堰形改进为之字形堰，使其宽度与航道宽度相等的研究。此外，特别值得一提的是，这种新型螺旋式通道结构可降低30-40%的施工成本。

A pipeline is usually constructed in the areas of where the slope is greater than 1/5. However, constructing pipelines results in problems such as blockage by driftwood or sand inside the initial portion of the pipeline, overflow of currents, and collapse of the pipeline. It is then very. difficult to remove the blockage.For these reasons, in this study an open channel structure was developed which can be constructed in areas with a 1/1 slope or when the curve angle of a channel is 90 degrees.This method of flow control is a newly developed technology. By altering the rectangular channel into a circular wall channel, the upward flow energy of high speed currents can be transformed into spiral flow energy, making the currents flow smoothly.It is possible to apply this technology of spiral flow type channel structure by constructing this system in mountains with steep slopes and curved channels or chutes. This method is practical in spillways located in narrow places, as well as in curved spillways of dams or reservoirs. At present, this new type spillway is in operation in one location.When the weir width of spillways is the same as the width of the arc section channel, flows can be controlled easily; but when the weir width is equal to or greater than the width of the channel, it causes overflows. Therefore, from now on studies on improving the shape of spillway weir to zigzag weir to make its width equal the width of the channel are planned on being carried out.Furthermore, it is worthy of special mention that this new spiral type channel structure can reduce the construction cost as much as 30-40%.