The effects of turbulence anisotropy and inhomogeneity on line‐of‐sight sound propagation

Line‐of‐sight wave propagation through isotropic, homogeneous turbulence has been studied by many previous researchers. A treatment for sound propagation, valid in the presence of both temperature and velocity fluctuations, was presented by Ostashev [Acoustics in Moving Inhomogeneous Media (E & FN SPON, London, 1997)]. Results for the statistical moments most frequently of interest were derived, in particular the correlation functions and variances of the log‐amplitude and phase fluctuations, the mean sound field, and the coherence function of the sound field. In the present paper, these equations are generalized for the case of line‐of‐sight sound propagation through anisotropic, inhomogeneous turbulence. The obtained equations do coincide with those known in the literature in the limit when only temperature fluctuations are present or turbulence is isotropic and homogeneous. Using Mann’s spectrum of shear‐produced atmospheric turbulence, the effects of turbulence anisotropy on the statistical moments of a sound field are studied. [This material is based upon work supported in part by the U.S. Army Research Office under Contract No. DAAG55‐98‐1‐0463.]