On Surface Gravity Waves in Heterogeneous Shear Flows.

Abstract

Two-dimensional surface waves in a stable stratified, inviscid and incompressible fluid, in which the mean flow varies only with depth, are studied. The vertical characteristic wavelength of these waves is assumed small compared to the characteristic scale-length of the fluid so that a geometric optics approximation yields a systematic expansion. Asymptotic results are obtained by the related W.K.B.J. method. In the absence of a critical level, at which the horizontal phase velocity relative to the mean flow vanishes, only discrete surface gravity wave mades exist. Each mode is reflected internally at a turning level as if a horizontal bottom exists. In contrast, continuous spectra of surface wave modes associated with the existence of critical levels are not affected by horizontal boundaries below their respective critical levels. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1969
Accession Number
AD0862256

Entities

People

  • Joseph P. Lau

Organizations

  • Florida State University

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Continuous Spectra
  • Contrast
  • Flow
  • Gravity
  • Gravity Waves
  • Phase Velocity
  • Shear Flow
  • Spectra
  • Surface Waves
  • Two Dimensional
  • Wave Phenomena
  • Waves

Fields of Study

  • Environmental science

Readers

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