IFD (Implicit Finite-Difference). Wide Angle Capability.

Abstract

In 1982, a general-purpose computer model, based on the implementation of an implicit finite-difference (IFD) scheme, was developed by Lee and Botseas at the Naval Underwater Systems Center (NUSC) for the solution of the parabolic-wave equation (PE). This model is being used to predict acoustic propagation loss in both range-dependent and range-independent environments. In this report, a recent improvement that extends the modeling of propagation angles from less than approximately 15 deg up to approximately 40 deg and the modifications that incorporate this improvement into the IFD model are presented. IFD calculations with and without this improvement are compared with normal-mode and fast-field-program (FFP) solutions for an isovelocity range-independent test case. Keywords include: Computer model, Implicit finite difference, Numerical methods, Parabolic wave equation, Propagation loss, Range dependent, Range independent, Underwater acoustics, and Wide angle.

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Document Details

Document Type
Technical Report
Publication Date
Oct 28, 1983
Accession Number
ADA163549

Entities

People

  • Ding Lee
  • George Botseas
  • Kenneth E. Gilbert

Organizations

  • Naval Underwater Systems Center

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Acoustic Fields
  • Acoustic Propagation
  • Acoustic Waves
  • Acoustics
  • Coefficients
  • Computers
  • Differential Equations
  • Environment
  • Equations
  • Frequency
  • Partial Differential Equations
  • Pressure Distribution
  • Standards
  • Underwater Acoustics
  • Wave Equations
  • Waves
  • Wide Angles

Readers

  • Acoustical Oceanography.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)