Accession Number : ADA296565

Title :   Development of a Multistream Acoustic Propagation Model Including Scattering by Turbulence.

Descriptive Note : Final rept.,

Corporate Author : ARMY RESEARCH LAB WHITE SANDS MISSILE RANGE NM

Personal Author(s) : Auvermann, Harry J. ; Reynolds, Richard L. ; Brown, Daniel M.

PDF Url : ADA296565

Report Date : JUN 1995

Pagination or Media Count : 79

Abstract : The objective of the ARL research effort in acoustic propagation is to provide the Army with a multistream model for investigating acoustic detection systems operating in a variety of realistic battlefield conditions. The first step is to account for scattering from turbulent regions of the atmosphere with an explicit algorithm. The turbulent region is considered to be a collection of vortices with a distribution of characteristic sizes and velocities and random orientation and position. Each vortex (turbule) is characterized as a known (or assumed) velocity distribution in three dimensional space. The scattering from each turbule is determined by solving the fluid equations. The contribution to the sound pressure level at the detector location of all turbules is summed up accounting for the propagation characteristics of the atmospheric medium. The algorithms devised to model the above picture of the turbulent region are then used in existing (or appropriately modified) propagation models. Progress in incorporating turbulence scattering into the Past Field Program (PFP) acoustic propagation model is recounted in this report. (MM)

Descriptors :   *ACOUSTIC WAVES, *ACOUSTIC DETECTION, *WAVE PROPAGATION, BATTLEFIELDS, SIGNAL TO NOISE RATIO, ORIENTATION(DIRECTION), TURBULENCE, VORTICES, METEOROLOGICAL DATA, THREE DIMENSIONAL, SOUND TRANSMISSION, WIND DIRECTION, WIND VELOCITY, REFRACTION, COMPUTER FILES, ACOUSTIC SCATTERING, ACOUSTIC VELOCITY, SOUND PRESSURE, ATMOSPHERIC ATTENUATION.

Subject Categories : Acoustic Detection and Detectors
      Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE