Closed equations for statistical moments of a sound field in a turbulent, refractive atmosphere near an impedance ground and their solutions

摘要

A parabolic equation for a sound pressure field is now widely used for numerical simulations of sound propagation near an impedance ground in a turbulent, stratified atmosphere. For different realizations of the temperature and wind velocity fields, the parabolic equation is solved numerically. Then, the statistical moments of a sound field are calculated from the ensemble of sound pressure realizations. We employ a different approach for calculating these statistical moments that can be advantaeous in many cases. Starting from a parabolic equation and using the Markov approximation, we derive closed equations for statistical moments (of arbitrary order) of a sound field propagating near impedance ground in a turbulent, stratified atmosphere. Then, the derived equations are solved analytically or numerically.