Calculation of Absorption Coefficient Using Average Temperature and Pressure.

Abstract

This note describes the investigation of an expression to be used in bottom bounce propagation models presently in use at NUWC Code D556. Recently an expression was developed to predict the acoustic absorption coefficient of seawater from the frequency, temperature, pressure and salinity. This expression was developed from a combination of existing equations in order to provide a single prediction expression valid under all operating conditions. In the past many methods for calculating the absorption coefficient have been used. These methods include the use of the surface temperature and 50 F in empirical expressions. This paper shows that it is necessary for the sake of accuracy to use the temperature averaged over the path of the propagating ray and to include the pressure term.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1968
Accession Number
ADA036609

Entities

People

  • H. R. Hall
  • L. P. Berger

Organizations

  • Naval Undersea Warfare Center

Tags

DTIC Thesaurus Topics

  • Absorption
  • Absorption Coefficients
  • Acoustic Absorption
  • Acoustics
  • Bottom Bounce
  • Coefficients
  • Computer Programs
  • Convergence Zones (Sonar)
  • Frequency
  • Losses
  • Sea Water
  • Static Pressure
  • Surface Temperature
  • Undersea Warfare
  • Underwater Acoustics
  • Underwater Sound
  • Warfare

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Calculus or Mathematical Analysis
  • Spectroscopy.