Nonlinear Water Waves Generated by Submarine and Aerial Landslides

TLDR

Nasa‑Vof2D is a nonlinear Eulerian code that solves the incompressible Navier‑Stokes equations by finite difference methods. The study modifies Nasa‑Vof2D to investigate the generation, propagation, and run‑up of water waves produced by landslides. The authors extended the code to allow time‑dependent bathymetry, enabling a sliding body of arbitrary geometry to move down any incline in two‑dimensional or axisymmetric configurations, and validated the model against experiments with a triangular body on a 45° plane. Computed wave profiles agree closely with experimental data, except when free‑surface turbulence occurs, which the numerical method cannot capture.

Abstract

The two‐dimensional hydrodynamics program Nasa‐Vof2D is modified to study the generation, propagation, and run‐up on the shore of water waves created by landslides. Nasa‐Vof2D, developed by the Los Alamos National Laboratory in Los Alamos, New Mexico, is a nonlinear Eulerian code, which solves the complete incompressible Navier‐Stokes equations by a finite difference method. The modification includes making the fluid domain boundaries (i.e., the bathymetry) time‐dependent. It allows a complex geometry box to slide down any incline, provided that the body kinetic is known and that the phenomenon is two‐dimensional or axisymmetric. To verify this numerical Nasa‐Vof2D extension, an experimental study on nonlinear waves generated by a two‐dimensional triangular body sliding a 45° inclined plane is conducted. The computed wave profiles show very close agreement with the experimental ones, except when free‐surface turbulence occurs, which the present numerical method cannot simulate.