Simulation of Impact Tsunami

by Michael Paine   24 July 1999
This animated GIF has been created from a video of a crude experiment to look at the feasibility of creating a model impact tsunami event using a bursting balloon. The idea is that the balloon creates a similar shaped crater (cavity) to that generated when an asteroid impacts into the ocean and explodes.

Bursting the balloon causes the crater to collapse. At first a central peak is generated when the in-rushing water meets at the centre. At this scale this peak appears to be almost twice as high as the depth of the initial crater. The peak collapses and then generates a radiating wave that reaches the side of the vessel (bath!). The centre oscillates up and down several times, producing a series of smaller waves.

The scale of this model is too small for it to be used to reliably predict a full size event (hydrodynamic similitude is not maintained) but this sort of modelling might be useful for verification of computer modelling at the same scale.

Here is the MPG file (300K) from the video-taped version (it is very quick - if you do the experiment yourself you will also need to videotape it and look at the results in slow motion)