游荡型河道阻力沿河宽分布的研究

Study on Flow Resistance Transverse Distribution in Braided River

阻力沿河宽分布的变化是造成游荡型河道主流频繁摆动的主要原因之一,掌握其变化规律是研究游荡型河流演变规律的关键。通过对游荡型河道成因及河道演变特性进行分析,结合黄河下游花园口-高村19541958年的水沙资料,考虑暴涨暴落的洪水、散体颗粒泥沙组成的床面形态以及剧烈变化的地形条件对阻力分布的影响,建立了适用于黄河下游游荡型河道的二维阻力公式。通过实测资料检验,计算值与实测值符合良好,表明该公式可以较好的反映游荡型河道阻力沿河宽分布的特性。

This paper presented the law of resistance transverse distribution in braided river, which is one of the key factors to study on the evolution rule of braided river. On the base of analyzing the characteristic of braided river, it is found that resistance transverse distribution is closely related to the great change discharge flood, different situation of riverbed composed by sand of small grain diameter and the landform change. According to the observed data from braided reach of Yellow River, the formula of resistance transverse distribution in braided river had been established after the relation and the law between above-mentioned three factors and resistance in the river has been confirmed. Compared with the observed data and the computed value, it is shown that the formula can represent the law of resistance transverse distribution in braided river.