Numerical Simulation Of Wave Run Up On Coastal Structures

It has long been a goal of coastal engineers to produce a computational wave model that is capable of accurately simulation wave runup. The establishment of a high-precision near-shore zone wave run-up model, as well as breaking wave model, not only has a higher degree of theoretical significance, but also has a direct significance of the project.Based on the mass consevvation equation and potential theory, the extended form of Boussinesq equations is derived by using the velocity at an arbitrary water depth as the independent variable, and several terms are added into govering equations to simulate the effect of bottom friction, wave breaking and subgrid turbulent mixing. So it can simulate the whole process of wave runup from deep water to seashore. A composite 4th-order Adams-Bashforth-Moulton scheme (utilizing a 3d-order Adams-Bashforth predictor step and a 4th-order Adams-Moulton corrector step) is used to step the model forward in time. Terms involving first-order spatial derivatives are differenced to o(Δx~4) accuracy utilizing a five-point formula. The difference scheme adopted by the truncation error is less than the non-linear equation in shallow water equations, can guarantee a higher accuracy of the numerical solution. In the numerical solution of equations, also introduced a numerical filtering techniques which effectively remove the non-linear due to the effects arising from the interaction of small harmonic wavelength, to ensure the accuracy of numerical.In order to verify the accuracy and applicability of the model, several numerical results from the model are compared with available physical experiment data. Comparsions show that numerical results agreed well with experimental data. So, the model has a good enough accuracy and applicability.