复式断面长河道洪水演进计算方法

为了更好地描述洪水波在长达1000km以上河道上演进的水力特性，对洪水演进计算方法进行了改进，建立了干支流同时演进的数学模型，实现了支流在时间过程上的同步汇入，并采用零流量水面线和描述精度更高的起点距－高程方法，计算基流时可选用更小的流量。模型验证表明，计算结果与实测资料吻合较好，应用本模型一水力参数复杂的超长天然河道的洪水演算具有精度高，收敛性好，工程应用简便，适用范围广的特点。

Computational Method of Flood Routing in Long Watercourse with Compound Cross-section

To describe the hydraulic characteristics of the flood routing in more than one thousand kilometers watercourse, the computational method is ameliorated in present paper. A mathematical model for simultaneous flood routing in the main river and tributaries is established. The model showes implements that the flood routing time of main channel is corresponding to those of tributaries. Moreover, the zero streamline and the relation of the distance from initial point and the elevation are presented. Thus it may select less discharge than former methods in calculating base flow. Model verification showes that the numerical results are in good agreement with measured data. The model is accurate, steady and convenient in application to the flow routing in natural rivers with complicated hydraulic parameters.