山区河流水位流量关系曲线研究

Study on Stage–discharge Relationship Curve in Mountain Rivers

受洪水涨落的水位流量关系呈现明显的绳套曲线,目前的研究大都基于平原河流,由于山区河流比降大、河床组成物质较粗,水流特性受到多方面因素的影响,故有些假设与实际河流情况不符,导致水位流量推求不太精确。因此本文考虑山区河流与平面河流的河床形态、泥沙粒径等方面的差异,引入了河道级别和泥沙粒径以区别山区河流与平原河流,结合简化后的圣维南方程组重新推导水位流量关系。通过山区河流和平原河流水文站的实测资料验证表明:该方法能较好地拟合相应河流横断面实测水位流量;在进行配线时,只需根据变化情况对参数做一些简单更正,具有实用性好、精度高以及适应性强等特点。

The relationship between stage and discharge caused by flood fluctuation shows a clear loop curve and most of the current researches are based on plain rivers. Due to larger river-bed slope, bigger size of sediment the difficult flow characteristics affected by many factors, some assumptions used are inconsistent so that the result is not very accurate. Therefore, this paper, considering the differences of river bed morphology and sediment particle size between mountain rivers and flat rivers, introduces new parameters of equations about river grade and sediment size and reintroduces the new stage–discharge relationship based on Saint–Venant equations. The results of examples application show this method can better fit the actual data of stage–discharge of the cross-sections in mountain rivers and plain rivers. When adapting the line, this method only need to make some corrections to the parameters according to the actual situation, which is more convenient to modify and has good practicality, high precision and strong adaptability.