Propagation of Weakly-Nonlinear Surface Water Waves in Regions with Varying Depth and Current.

Abstract

This report represents a study of the equations governing the propagation of weakly nonlinear waves in regions where currents exist and where the depth and current are allowed to vary. After deriving a velocity potential applicable to propagating surface waves according to the Stokes expansion, the Lagrangian governing wave motion in the propagation space is derived. A consistent perturbation scheme then leads to the equations governing the wave and current motion at each order in the Stokes series. After neglecting time dependence of the wave amplitude, parabolic equations governing the combined refraction and diffraction of Stokes waves of small amplitude are developed and used to calculate the wavefields for several representative cases illustrating the importance of nonlinear effects. The computational models are verified by comparison to laboratory data of wave amplitude for a wavefield focussed by a submerged shoal, and it is found that the nonlinear model accounts for the major discrepancies found between linear model results and the laboratory data. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1983
Accession Number
ADA132593

Entities

People

  • James Thornton Kirby Jr

Organizations

  • University of Delaware

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Boundary Layer
  • Civil Engineering
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Diffraction
  • Errors
  • Fluid Flow
  • Geometry
  • Nonlinear Dynamics
  • Standing Waves
  • Two Dimensional
  • Variational Principles
  • Wave Equations
  • Wave Propagation
  • Waveforms

Fields of Study

  • Mathematics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Dynamics.

Technology Areas

  • Space