Development of a Parabolic Approximation for the Computation of Propagation Loss in a Range-Dependent Environment

  • B. Grandvuillemin
Part of the NATO Conference Series book series (NATOCS, volume 16)


We propose to solve the Helmholtz equation by means of the parabolic approximation in a two-dimensional environmental propagation. We make clear the solution for a quadratic development of the propagation operator which allows us to take into account a larger angular aperture of the source. The numerical solution is given by an algorithm of finite differences using the Crank-Nicholson method. The problem of rectilinear, horizontal and oblique interfaces between two fluid media is solved. The problem of the medium where the sound velocity profile changes with range is treated by conditions of continuity between two media with the given sound speed profiles. The first results of numerical simulations executed on the VAX 11/780 and the array processor FPS 164 are presented. They show the ability of the model to describe the importance of environmental variation on propagation.


Helmholtz Equation Mesh Point Sound Field Source Depth Paraxial Approximation 
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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • B. Grandvuillemin
    • 1
  1. 1.GERDSMLe BruscFrance

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