Numerical Modeling and Experimentation of the Dam-Overtopping Process of Landslide-Generated Waves in an Idealized Mountainous Reservoir

Abstract

A two-dimensional coupled solid-fluid numerical model was modified and applied to simulate the dam-overtopping event of landslide-generated waves in an idealized reservoir. The model employed was based on the two-dimensional Reynolds-Averaged Navier-Stokes (RANS) in a vertical plane with the k−ε equations for turbulence closure. The motion of the solid landslide was modeled using the equation of motion for rigid body, and the free surface was tracked using volume of fluid (VOF) method. For model validation, experiments were conducted for the case of dam overtopping in an open channel. Particle image velocimetry (PIV) was used to measure velocity variations of the first wave during dam overtopping in one field of view (FOV), and wave gauges were used to record variations of the free-surface elevation at three selected locations in the open channel. The calculated and measured data comparisons were performed for time histories of surface elevation, surface profile, and vertical velocity distribution, and showed reasonable agreement. Following model validation, the numerical model was also used to illustrate the velocity and turbulence kinetic energy features during wave-generation and overtopping processes.