Influence of horizontally - random bottom structure on acoustic intensity

نویسندگان

  • M. J. Jacobson
  • W. L. Siegmann
چکیده

Effects of a model for random bottom structure on acoustic intensity in isospeed shallow water are studied. The randomness is due to stochastic variations in the bottom density and sound speed in the horizontal direction beneath a plane water-bottom interface. Ray geometry, spreading loss, and bottom loss and phase shift are examined in order to derive formulas for mean intensity and the variance of intensity. The expressions obtained are sufficiently general to permit their use with different bottom-acoustic models of sound reflection. In this paper, for illustrative and comparative purposes two such models, one developed by MacKenzie and the other by Rayleigh, are considered. The distinctive acoustic consequences of bottoms of different density mean, variance, and horizontal correlation are discussed, as are comparisons of results for the two bottomreflection models. Intensity moments are obtained also for differing sourcereceiver range and water depth.

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تاریخ انتشار 2015