Numerical analysis of dam-break waves propagating over dry and wet beds by the mesh-free method

摘要

Climate change increases the probability of dam-break flooding, making the prediction of flooding zone and dam-break wave crucial for the evacuation of people in hazardous areas. However, the propagation of dam-break waves can be affected by different downstream bed conditions such as obstacles, dry and wet beds. In this study, a mesh-free method is employed to simulate dam-break wave spreading in different bed configurations. The mesh-free method is good at capturing the free surface in the dam-break flow. In the numerical method, an explicit calculation for the pressure field is used and the spatial operators are based on the Moving Particle Semi-implicit method (MPS). The mesh-free method is validated to simulate the dam-break flow by comparing to available experimental measurements. The validated method is then used to simulate the dam-break wave propagating over the downstream wet beds with different depths. The effect from the combination of dry and wet bed for the dam-break wave is also investigated by the mesh-free method. In the simulations, the flow characteristics including free surface, flow pattern, and wavefront movement, and bed shear stress are presented and discussed.