Numerical predictions of laboratory-generated tsunami waves

Abstract

This article presents numerical simulations of tsunami waves that are generated using different experimental techniques in laboratory tests. Comparisons of the numerical predictions of the tsunami wave shapes with different experimental measurements of the wave shapes have been carried out, and a good agreement was obtained. Four different laboratory techniques to create tsunami waves were examined: a sudden release of a water column, a horizontal or vertical motion of a piston, and a rotation of a rigid plate. Comparison of waves of the same height that are formed by these four different methods shows that the horizontal piston motion produces the shortest wave, and the vertical piston motion produces the longest wave. The wave produced by a plate rotation is similar to the wave caused by the "water column release," but it is slightly longer. It was found that different techniques produce different wave characteristics; therefore, selection of the proper laboratory technique requires some considerations including a comparison with the required real tsunami wave that should be simulated. It should be emphasized that this research aims at simulating the tsunami waves that are produced by different common laboratory techniques; however, it refrains from assessing the adequacy of any of this techniques to properly represent a real specific tsunami wave. Further to developing the computational procedures for tsunami wave simulations, this article extends the numerical study to examine the interaction of a tsunami wave with a rigid wall and investigate the dynamic pressure distribution on the wall surface. It was found that the peak pressure of a tsunami wave acting on a rigid wall that is produced by the horizontal piston has the lowest magnitude (among the waves of the same height, caused by these four techniques), while the pressure due to a rotational plate has the highest magnitude.