Numerical Predictions of Laboratory Tsunami Waves

Abstract

The paper aims at development of a numerical approach to simulate tsunami waves that are produced with different techniques in laboratory experiments. The present study also examines the interaction of a tsunami wave with a rigid wall and estimates the dynamic pressures acting on the wall surface. It should be emphasized that this research aims at simulating the tsunami waves but there is no intention to examine the correspondence of the different lab waves that are produced by different experimental devices with a tsunami real wave. Comparison of the numerical prediction of a tsunami wave shapes with the experimental measurement of the wave shapes shows good correspondence. Four types of laboratory techniques to create laboratory tsunami waves were examined: a sudden release of a water column, horizontal or vertical motion of a piston and rotation of a rigid plate. Comparison of waves of the same height that are formed by these four methods shows that the horizontal piston motion device produces the shortest wave, and the vertical piston motion device produces the longest wave. The wave that is produced by plate rotation is similar to the wave produced by "water column release", but it is slightly longer. The peak pressure on the rigid wall produced by the horizontal piston, is of 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 largest magnitude. It was found that different techniques produce different wave characteristics; therefore selection of the proper laboratory technique requires some consideration and comparison to the required real tsunami wave that should be simulated