Applied Underwater Acoustics

Chapter 3

Sound Propagation Modeling

S. Ivansson     Swedish Defence Research Agency, Stockholm, Sweden

Abstract

This chapter presents some common sound propagation modeling methods: ray tracing, wave number integration, normal-mode expansion, parabolic equation approximation, and finite-difference (FD) and finite-element (FE) discretization. Although the main focus is on frequency-domain methods for a fluid medium, fluid–solid media are treated for some methods, and some FD and FE time-domain techniques are included. Except in a final section on 3-D modeling, the common 2-D case is assumed, with cylindrical symmetry around a vertical source axis. The reflection-coefficient matrix method (invariant embedding) recurs, with essentially the same formalism, ...