Numerical Simulation of Dynamic Process of Dam-break Flood and its Impact on Downstream Dam Surface

Dam-break floods are among the most devastating natural disasters, causing significant casualties and property losses globally. However, current research primarily emphasizes macroscopic quantities such as water level, with a limited focus on detailed spatiotemporal hydrodynamics, particularly downstream flood impacts. This study employs a depth-integrated shallow water model based on the finite volume method to examine the influence of dam spacing, bed slope, and upstream and downstream water depths on flood dynamics processes and their impacts on downstream dams. The key findings include: (1) Larger dam spacings delay flood arrival downstream, increasing the water depth, Froude number, discharge, shear stress, velocity, and impact pressure. (2) Steeper bed slopes increase the Froude number, shear stress, velocity, and impact pressure, while the discharge and water depth exhibit inconsistent changes at different gauge points. As the bed slope increased from 4° to 12°, the impact pressure almost doubled. (3) Higher upstream water levels increase the water depth, discharge, velocity, and downstream impact pressure but reduce shear stress, with inconsistent changes in the Froude number. The peak impact pressure at ho = 0.25 m is more than two times higher than that when ho = 0.1 m. (4) Increased downstream initial depths increase the downstream water depth, discharge, and impact pressure while reducing shear stress, with similar changes observed in velocity and Froude number. Overall, this study provides new insights into the hydrodynamic processes of dam-break floods and their impacts on downstream dam surfaces.