Accession Number : ADA316034

Title :   Research Ambient Noise DIrectionality (RANDI) 3.1 Physics Description.

Descriptive Note : Final rept.,

Corporate Author : NAVAL RESEARCH LAB STENNIS SPACE CENTER MS

Personal Author(s) : Breeding, J. E., Jr. ; Pflug, Lisa A. ; Bradley, Marshall ; Walrod, Melanie H.

PDF Url : ADA316034

Report Date : AUG 1996

Pagination or Media Count : 37

Abstract : A description is presented of the physics behind the Research Ambient Noise Directionality (RANDI) model version 3.1. The RANDI 3.1 model can be used to predict ambient acoustical noise levels and directionalities at low to midfrequencies for shallow and deep water environments. Ambient noise due to shipping, wind, flow noise, and system noise are considered. Shipping noise can be calculated for highly variable environments and is done using either a finite element or split step parabolic equation. Local wind noise is computed based on the range independent theory of Kuperman Ingenito, including both discrete (normal modes) and continuous spectra. Navy Standard and historical data bases are used to describe the environment. Sample outputs are presented to illustrate products of the model.

Descriptors :   *AMBIENT NOISE, *UNDERWATER ACOUSTICS, DATA BASES, SHIP NOISE, FINITE ELEMENT ANALYSIS, WIND, SHALLOW WATER, ACOUSTIC ARRAYS, FLOW NOISE, DIRECTIONAL.

Subject Categories : Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE