Accession Number:

AD0781230

Title:

GRASS: A Digital-Computer Ray-Tracing and Transmission-Loss-Prediction System. Volume 1. Overall Description,

Descriptive Note:

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s):

Report Date:

1973-12-21

Pagination or Media Count:

75.0

Abstract:

GRASS Germinating Ray-Acoustics Simulation System is a set of linked digital computer programs Fortran, or modules. These modules 1 convert salinity, temperature, and depth STD data to sound-speed profiles 2 interpolate and extrapolate the sound-speed field 3 generate Calcomp or Gerber plots of the sound-speed profiles 4 generate contour and three-dimensional isometric plots of the sound-speed field 5 trace rays and calculate intensities 6 generate ray diagrams and 7 construct plots of the calculated transmission loss versus range. The system can handle multiple profiles and a linear-segmented bottom profile. It is presently running on a CDC 3800. This report, the first of a two-volume set, includes an overview of each module, outlines the methods used in the calculations, provides the results of some test cases, makes some recommendations for improvement, and briefly compares ray and normal-mode theories. Author

Subject Categories:

  • Computer Programming and Software
  • Acoustic Detection and Detectors
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE