桥渡壅水平面二维数学模型模拟研究

Research on plenar 2-D mathematical model of bridge pier choked flow

本文根据圣维南基本方程组,建立了平面二维非恒定流桥渡数学模型方程,通过坐标变换,以边界拟合坐标生成二维均匀正交网格,在交错网格上采用交替方向的全隐差分格式进行离散化代数方程计算。通过桥渡流场的实例计算,在水位、流速分布、分流比和桥渡壅水等方面取得了令人满意的结果,该数学模型对于弥补和配合物理模型进行桥渡问题的研究具有重要作用。

Based on the Saint-Venant equations, a two-dimensional plenar unsteady flow mathematical model for bridge pier choked flow movement was set up. By adopting a coordinate transformation, the boundary-fitted corrdinate system with even and perpendicular grids was formed. The governing equations were discretized on staggered grids and solved with ADI finite difference scheme.The model was applied to calculate practical flow field around bridges. The results, including water level, velocity distribution, discharge ratio between branches and choked flow field were satisfactory.This mathematical model can be used as a matching tool to physical model testing in studying bridge pier choked flows.