三峡建库后芦家河水道的演变预测

Prediction for evolution of Lujiahe water course in the middle Yangtze River after founding of the Three Gorges Project

针对长江中游芦家河河段的特性，建立了适合该河段的平面二维水流数学模型，用芦家河水道的实测资料验证表明，计算值在水位、流速、流向等方面均与实测情况一致，说明该模型能够较好地反映芦家河水道的水流运动特性．对常用的五家非均匀沙起动流速公式进行了分析和检验；应用上述水流数学模型及修正后的非均匀沙起动流速公式，对芦家河水道进行了三峡建库后河床极限冲刷状态计算和枯水通航条件预测．

According to the characteristics of Lujiahe channel in the middle reach of the Yangtze River, a two-dimensional mathematical model for flow was established,and has been verified by the field data of Lujiahe channel.The results show that the water elevation,flow velocity and flow direction of the channel can reflect the flow characteristics.In addition,a comprihansive analysis of five critical motion formulae of nonuniform sand has been made.The mathematical model and the modified critical motion formulae have been used to predict the limiting erosive condition of the Lujiahe channel after the Three-Gorges dam is constructed and the navigation condition at low stage also was estimated.