黄河下游高村-陶城铺河段边界阻力能耗与河床稳定性分析

Energy dissipation of boundary resistance and stability analysis of riverbed of Gaocun to Taochengpu reach in lower Yellow River

从河床边界阻力能耗角度研究河床形态调整规律,引入河床稳定性指标,探讨与边界阻力能耗率的相关性。以黄河下游高村至陶城铺河段为研究区域,采用实测资料、理论解析与数值模拟相结合方法,基于不同年份河道地形,计算出不同流量条件下的水力要素与边界阻力能耗率,分析河床形态调整过程及边界阻力能耗率响应,讨论了边界阻力能耗率与河床稳定性关系。结果表明:边界阻力能耗率沿程均值和波动强度随着流量增大而增大;阻力能耗率随着过水面积或宽深比呈先减小后增大趋势,且与河床稳定指标呈正相关关系,但能耗率趋近最小值时,河床也可能发生下限失稳。通过优化河床断面形态,维持河床稳定情况下寻求边界阻力能耗率最小,能够提高河槽的输水输沙能力。

The regulation of riverbed morphology adjustment is explored,in view of riverbed boundary resis⁃tance energy dissipation,and the correlation between energy dissipation rate and riverbed stability index is analyzed.Taking Gaocun to Taochengpu reach in the lower Yellow River as the research area,based on the topography of the river in different years,the energy dissipation rate and hydraulic elements under dif⁃ferent discharges are calculated by using the methods,including the measured data,theoretical analysis and numerical simulation.It is found that the mean value and fluctuation intensity of energy dissipation rate increased with the increase of the discharge;the energy dissipation rate displays a trend to decrease firstly then increase with the increasing of the flow area or width depth ratio.In addition,there is signifi⁃cant positive correlation between the energy dissipation rate and the riverbed stability index.However,the riverbed may also not remain stable,when the energy dissipation rate approaches the minimum value.By optimizing the section configuration of the river bed and seeking the minimum energy dissipation rate of the boundary resistance under the condition of the river bed remains stable,the water and sediment transport capacity of the river channel will be improved.