Propagation of a solitary wave over rigid porous beds

The unsteady two-dimensional Navier-Stokes equations and P avier-Stokes type model equations for porous flows were solved numerically to simulate the propagat on of a solitary wave over porous beds. The free surface boundary conditions and the interfacial boundi ry conditions between the water region and the porous bed are in complete form. The incoming wav !s were generated using a piston type wavemaker set up in the computational domain. Accuracy o: the numerical model was verified by comparing the numerical results with the theoretical solutior;. The main characteristics of the flow fields in both the water region and the porous bed were disc issed by specifying the velocity fields. Behaviors of boundary layer flows in both fluid and porous be i regions were also revealed. Effects of different parameters on the wave height attenuation were StL Jied and discussed. The results of this numerical model indicate that for the investigated incident wav ! as the ratio of the porous bed depth to the fluid depth exceeds 10, any further increase of the porous ied depth has no effect on wave height attenuation. (c) 2008 Elsevier Ltd. All rights reserved.