SPH SIMULATION OF FLOW FIELD AND BEHAVIOR OF ARMOR UNITS BEHIND BREAKWATER DURING TSUNAMI OVERFLOW

Abstract

 Flow field behind a breakwater during tsunami overflow was reproduced using DualSPHysics, which is a CFD code based on the SPH method, and the results were verified by comparing with the experimental data. In addition, behavior of tetrapods behind the breakwater against tsunami overflow was also reproduced. As for the flow field, even under uniform condition in the channel width direction, the 2D and 3D calculations showed different results, and the 3D calculation agreed better with the experimental results. In addition, the flow field was significantly affected by the artificial viscosity, and the results were generally good when the artificial viscosity coefficient was set to 0.01. As for the behavior of the armor units, the initial damage, such as the detachment of a single block, was generally reproduced, but the behavior, such as the sliding of the entire slope at a large overflow depth, was not reproduced.