Interaction of wet dam-break flows with a structure: on the effects of surface tension and gate opening velocity in water surface evolution using MPS method

Abstract

This paper presents an experimental and numerical investigation of the interaction of wet dam-break flows with a fixed structure. These flows presented breaking features and caused bow run-up and shipping water events on the deck of the structure. Wet dam-break experiments were performed using high-speed video to capture the stages of wave generation, interaction with the structure and propagation on its deck. Two different incoming flows were generated, varying the freeboard, and keeping the same wet dam-break ratio. These were numerically simulated using Moving Particle Semi-implicit (MPS) method. The purpose was to compare MPS numerical simulations based on two surface tension models previously proposed in the literature and a geometric-based surface tension model proposed in this work, this to improve free surface performance to represent breaking wave features more realistically. First, the different approaches were compared with experimental results. Then, the proposed model was implemented to analyze the effect of the velocity applied to gate opening on the water surface during wave generation, wave-bow interaction and water propagation over the deck. The distribution of particles, pressure and velocity fields was presented in this analysis. Results showed that the proposed surface tension model performed well in representing the free surface. It was seen that surface tension effects can be relevant during the wave formation effects. Furthermore, it was verified that variating the gate opening velocity, dynamic interactions of the resulting waves with the structure was affected, causing energetic processes variations. It is recommended to consider this velocity for validation purposes.