Shock wave propagation along constant sloped ocean bottoms

Area of Science:

• Underwater acoustics
• Computational physics
• Wave propagation modeling

Background:

• The nonlinear progressive wave equation (NPE) models long-range shock propagation.
• Current NPE models struggle with sloping fluid-fluid interfaces.
• Accurate modeling is crucial for underwater acoustic applications.

Purpose of the Study:

• To adapt the NPE for range-dependent environments with sloping bathymetry.
• To analyze the influence of sound pressure levels on nonlinear steepening.
• To investigate the impact of sediment layers on blast wave propagation.

Main Methods:

• Utilized a rotated coordinate system to align sloping interfaces with computational axes.
• Applied appropriate interface, initial, and boundary conditions in the rotated system.
• Quantified nonlinear steepening effects across different sound pressure levels and domains.
• Simulated blast wave propagation through thin sediment layers.

Main Results:

• The rotated coordinate system effectively handles sloping interfaces in the NPE.
• Determined pressure thresholds where linear acoustic models become insufficient.
• Identified significant effects of thin sediment layers on blast wave propagation.

Conclusions:

• The adapted NPE provides a robust framework for modeling underwater acoustics in complex geometries.
• The findings offer insights into the limits of linear models and the impact of environmental factors on shock wave propagation.