The Structure of Turbulence and Other Motions Beneath an Air-Water Interface

Abstract

Both physical experiments and numerical simulation experiments were used to study three-dimensional, unsteady, real-fluid flows beneath the alr-water interface. The focus of the numerical work was the kinematics of the interaction between surface waves and a turbulent current. The numerical method produces a time-accurate, large-eddy simulations of an unsteady turbulent free-surface flow in three space-dimensions. The simulations show that the turbulence in the near-surface region is enhanced by the interactions between non-breaking waves and a turbulent shear current. A novel measurement technique, digital particle tracking velocimetry (DFTV), was developed and used to make near-surface measurements of the velocity field in wavy and non-wavy open channel flows. This approach is based on cross-correlation digital particle image velocimetry (DPIV) and results in significantly improved resolution and accuracy. In particular, this approach allows for the direct measurement of mean squared fluctuating gradients, and thus several important components of the turbulent dissipation.

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Document Details

Document Type
Technical Report
Publication Date
Aug 31, 1997
Accession Number
ADA346510

Entities

People

  • Robert Lynnwood Street
  • Stephen G. Monismith

Organizations

  • Stanford University

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Accuracy
  • Boundary Layer
  • Channel Flow
  • Fluid Flow
  • Fluid Mechanics
  • Large Eddy Simulation
  • Layers
  • Measurement
  • Mechanics
  • Mixing
  • Physics
  • Physics Laboratories
  • Standing Waves
  • Stratified Fluids
  • Surface Waves
  • Three Dimensional
  • Turbulent Flow

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Computational Fluid Dynamics (CFD)
  • Fluid Dynamics.

Technology Areas

  • Space