Accession Number:

ADA029927

Title:

Effect of Nonlinearity on Noise Propagation,

Descriptive Note:

Corporate Author:

TEXAS UNIV AT AUSTIN APPLIED RESEARCH LABS

Report Date:

1974-01-01

Pagination or Media Count:

15.0

Abstract:

A previous study of plane waves of noise has been followed up by extending the analysis to the problem of noise propagation in open media. Several different aspects of the problem were examined. First, our plane wave analysis was extended to cover spherically and cylindrically spreading waves. Then scaling rules concerning the effects of frequency and amplitude were determined. Consideration of the unique properties of the random sawtooth wave led to the conclusion that the spectrum of very intense noise has a high frequency rolloff that approaches 6 dBoctave. The role played by phase of the noise signal was investigated by computing the distortion of several noise signals having the same spectrum but different phase characteristics. Phase was found to be relatively unimportant for the cases studied. Finally, distortion computations were made using a particular example of actual jet noise, noise of not very high intensity from the British-French Concorde. In this particular case nonlinear effects did not prove to be very important. Author

Subject Categories:

  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE