Development of Turbulence Models for Free-Surface Flows

Abstract

The goal of this effort was to improve the ability to predict the free-surface flow in the near field of surface ships. The specific objectives were: to develop modeling approaches appropriate to the near-surface region in turbulent free surface flows and to obtain data for validation of CFD predictions of free-surface turbulent flows. The main results of this study can be summarized as follows: (1) The framework outlined in Hong & Walker (2000) was shown to be reasonable for turbulent free-surface flows. (2) The surface current is caused by a combination of turbulent surface fluctuations and turbulence anisotropy, with surface fluctuations dominating in high-Froude-number flows, and anisotropy otherwise. (3) The surface fluctuation effects can be approximated by a stress boundary condition. (4) A computational approach for predicting turbulence-generated waves was developed and the results compared favorably to experimental data. (5) Surface fluctuation measurements were carried out for a free-surface jet flow and the p.d.f. for the surface elevation was shown to be relatively Gaussian. (6) A method for measurement of the directional wave spectrum was developed and implemented and the directional spectrum of turbulence generated waves was characterized for a free-surface jet.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2003
Accession Number
ADA416945

Entities

People

  • David T. Walker

Organizations

  • University of Michigan

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Anisotropy
  • Boundaries
  • Computational Fluid Dynamics
  • Computational Science
  • Directional
  • Elevation
  • Equations
  • Experimental Data
  • Flow
  • Fluid Flow
  • Froude Number
  • Jet Flow
  • Marine Engineering
  • Measurement
  • Near Field
  • Turbulence
  • Turbulent Flow

Fields of Study

  • Physics

Readers

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