溃坝波在弯曲河道中传播的二维数值模拟

为分析溃坝波在天然弯曲河道中传播的特点,建立了跟踪河道走向的正交曲线坐标系,并通过坐标变换、简化和水深积分推导出了曲线坐标系下的二维浅水方程.利用能较好地适应水流间断性质的Godunov差分格式,对控制方程在二维矩形区域上进行离散求解,模拟溃坝波在不同弯曲度弯道中的传播过程.结果表明,该模型能够简便、快速、有效地模拟弯道溃坝波的传播,河道的弯曲会对溃坝波传播的速度以及水面形态产生影响.

Two-Dimensional Numerical Simulation of Dam-Break Wave Propagation in Channel Bends

To analyze the feature of dam-break flow in natural channel bends,channel-fitted orthogonal curvilinear coordinate system is established and two-dimensional shallow water equations are derived in this system through coordinate transformation,simplification and depth integration.These equations are then solved in a rectangular domain using Godunov type finite-difference scheme,which is adapted well to the discontinuity of dam break wave.The propagation of dam-break wave in channel bends with various curvatures is simulated.The results indicate that this model can simulate propagation of dam break wave in channel bends concisely,rapidly and effectively.The curvature of channel bends may have influence on both propagation speed of dam break wave and the fluctuation of water surface.