Numerical investigation of solitary wave attenuation and mitigation caused by vegetation using OpenFOAM

Wave energy can be reduced by coastal vegetation, which is an important aspect of coastal protection engineering. The effect of vegetation characteristics on solitary wave propagation and attenuation is numerically investigated in this study. A 3D numerical model is established based on the Reynolds Averaged Navier Stokes (RANS) equations combined with k-omega shear stress transport (SST) turbulence model, and the Volume of Fluid (VOF) method is used to capture the free water surface. This model is first validated by a series of physical experimental results with high accuracy. Subsequently, the model is used to simulate the interaction between solitary waves and submerged vegetation with different densities, submergence ratios, and distribution modes. The results indicate that the density and submergence ratios of submerged vegetation significantly affect the propagation and attenuation of solitary waves under uniform distribution modes. Compared with the condition of the uniform distribution mode, the solitary wave dissipates more energy after passing through the vegetation zone under the non-uniform distribution modes. Large differences in velocity fields are found for uniform/non-uniform distribution modes, which contribute to understanding the wave dissipation influenced by vegetation characteristics.