Numerical simulation of nonlinear transient waves and its validation by laboratory data

Nonlinear transient waves are numerically calculated in time domain and validated by laboratory data. The simulation is based on potential flow theory and performed in a two dimensional numerical wave tank with piston-type wave generator. A finite element method developed by Wu and Eatock Taylor (1994a, 1994b) is used to determine the velocity potential, which satisfies the Laplace equation for Neumann and Dirichlet boundary conditions. To develop the solution in time domain the fourth-order Runge-Kutta method is applied. The paper presents numerical results of the potential and velocity distributions of a transient wave train. The calculated and measured surface elevation history at different positions and the related Fourier spectra are compared. Orbital tracks of particles as well as the development of the maximum and minimum surface elevation are shown. Good agreement of numerical and experimental results with wave heights up to 1.1 m is observed.