Parallels in scattering research between architectural and underwater acoustics

Abstract

Acoustical scattering is a central area of research in the fields of underwater and architectural acoustics. Although the mathematical formulation of the scattering problem is common to both fields, their goals and environments have motivated divergent analysis techniques, and quantities associated with the pressure field due to scattering. One of the primary differences is the role of statistical averaging. Ensemble-averaged quantities can often be used in ocean acoustics because the seafloor may have statistically homogeneous roughness and geoacoustic properties over large areas. In the built environment, the acoustic field can interact many times with a single acoustic diffusor, and deterministic properties of the scattered field are of greater import. Acoustical quantities such as the scattering cross section, scattering coefficient, and the diffusion coefficient will be defined and compared. Examples will be given that highlight cases when ensemble-averaged quantities can aid or hinder design of acoustical diffusors, depending on the design constraints.