Method for Determining Local Inner and Outer Boundary Layer Length Scales from Drag Measurements in High Reynolds Number Turbulent Flows

Abstract

This patent application discloses a method for determining inner and outer boundary layer length scales from a succession of drag measurements of a cylindrical body to estimate flow noise and for computational modeling of the dynamics of towed arrays in a fluid medium. A succession of measurements of the total drag on a cylinder under tow at uniform known conditions (i.e., flow speed, fluid density, fluid viscosity, cylindrical body geometry) is taken. After each measurement, the cylinder is truncated by a fixed amount, and the process is repeated for the length of the cylinder. The measurements provide a spatially and temporally averaged measure of the mean wall shear stress and momentum thickness, from which the inner and outer length scales can be determined. The inner and outer boundary layer length scales may then be used for estimation of flow noise on towed cylindrical bodies and arrays.

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Document Details

Document Type
Technical Report
Publication Date
Dec 20, 2005
Accession Number
ADD020235

Entities

People

  • William L. Keith

Organizations

  • United States Department of the Navy

Tags

Communities of Interest

  • Ground and Sea Platforms
  • Sensors
  • Weapons Technologies

DTIC Thesaurus Topics

  • Arrays
  • Boundary Layer
  • Computational Modeling
  • Flow
  • Flow Noise
  • Geometry
  • Layers
  • Load Cells
  • Measurement
  • Noise
  • Patents
  • Reynolds Number
  • Shear Stresses
  • Thickness
  • Towed Arrays
  • Towed Bodies
  • Turbulent Flow

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Electrical Engineering
  • Fluid Dynamics.