Direct and inverse problems in radiation of sound from discrete random sources on two coaxial rings
Abstract
An analytical model consisting of two ring sources of sound is developed to study the direct radiation in terms of correlation, coherence, and phase and also to aid in solving the inverseradiation problem of determining the noise source in terms of farfield measurements. The rings consist of discrete sources which are either monopoles or quadrupoles with Gaussian autocorrelations. Only adjacent sources, both within and between the rings, are correlated. Results show that from the farfield information one can determine when the sources are compact or noncompact with respect to the acoustic wavelength and distinguish between the types of sources. In addition, from the inverseradiation approach one can recover the center of mass, the location and separation distance of the ring, and the respective diameters.
 Publication:

Acoustical Society of America Journal
 Pub Date:
 December 1979
 DOI:
 10.1121/1.383620
 Bibcode:
 1979ASAJ...66.1876M
 Keywords:

 Far Fields;
 Noise Generators;
 Noise Measurement;
 Random Vibration;
 Ring Structures;
 Sound Fields;
 Autocorrelation;
 Cross Correlation;
 Mathematical Models;
 Monopoles;
 Noise Propagation;
 Phase Coherence;
 Quadrupoles;
 Spectral Correlation;
 Acoustics