Multi-Solitary (Tsunami) Wave

Tsunami waves cause significant losses to coastal regions, and they transform into a series of solitary waves or undular bores over a mild slope. Yet, the nonlinear dispersion of water waves and wave deformation over varying bottom topography make the modeling of tsunami wave propagation extremely hard. It is therefore important to combine both large scale lab simulations of solitary waves, and numerical modeling to capture nonlinearity in tsunami dynamics. With this work on examination of the fully nonlinear model named FUNWAVE-TVD, which solves Boussinesq equations to high order accuracy, our research compared numerical simulations with lab experiments on how wave breaks and collides when travelling up a slope, which is very close to the real-world situation and tsunami formalization.

We first simulated 1-D solitary waves traveling up a slope and then validated with solitary wave runup datasets from well-controlled laboratory experiments. Numerical results show that the runup of multi-solitary waves with uniform initial amplitude over a 1:20 slope varies with each individual wave. Then, we extended the simulations of multi-solitary wave evolution and overtaking collisions over a slope for the cases of unequal initial wave amplitude.

Key questions being asked:

• Wave breaking location of each solitary wave
  
  
• Runup height of multi-solitary wave
  
  
• Convergent runup height