Numerical Simulation of Acoustic Waves Propagation in an “Atmosphere–Forestland–Ground” System

Resumo

Under study is the problem of numerical simulation of acoustic waves propagation in a two-dimensional inhomogeneous medium represented by the “atmosphere–forestland–ground” model. A specific feature of the simulation is the introduction into the basic equations of acoustics of a linear damping function that characterizes the energy loss of the acoustic wave with respect to afforestation. The problem is considered of interaction between the acoustic waves incident at a given angle from the atmosphere to the “forestland–ground” boundary and the seismic waves arising in the ground. The issue of the forestland influence on the levels of acoustic and seismic waves is investigated. In particular, the impact of the friction coefficient on the attenuation rate of acoustic oscillations in the forestland is estimated. The algorithm and software are developed and implemented for calculating the acoustic pressure levels in various media, by using the wave equation for the atmosphere, Euler’s gas dynamics equations for the forestland, and the elasticity equation for the ground. The results of numerical experiments are presented as instantaneous images of the wave field.