矩形连续弯道流场简化计算数学模型

The Computation of 3-D Flow Fields in Channel with 2-D Plane Numerical Model

运用新近的解析-数值势流理论方法,生成正交数值网格,用差分法计算出平面二维流场。然后,按将水力半径分为河床阻力水力半径和河岸阻力水力半径的方法和对数流速分布公式,计算垂向流速分布。将平面二维流场计算和垂线流速分布计算很好地结合起来,形成了特殊的渠道三维流场计算方法。此方法边界适应能力强,计算时间短,内存少。已用于计算连续弯道,其结果令人满意。

The recent potential flow theory and finite-difference method are applied to generate orthogonal numerical grids and to compute two-D plane flow fields. Then the method, which divides hydraulic radius R into river bank hydraulic radius Rw and river bed hydraulic radius Rb, and the formula of logarithmic velocity distribution are used to compute velocity distribution in vertical line. The computation of two-D plane flow fields and the computation of velocity distribution in vertical line are combined very well, which constitutes the special three-D flow fields computation in this paper. A sequent bend is taken as a computational example, and the computational results of flow fields coincide well with the measured data.