TURBULENCE MEASUREMENTS IN A TIDAL CURRENT.

Abstract

Measurements were made of the component of turbulent velocity along the axis of a 3-knot tidal current 1.5 meters below the water surface using a ducted impeller current meter. Values of the one-dimensional energy spectra were computed on a digital computer at wave numbers from 0/cm to 0.157/cm. The composite energy spectrum obtained from the individual spectra was of the -5/3 power law form predicted by the Kolmogoroff hypothesis for wave numbers from 0.01/cm to 0.026/cm. At higher wave numbers the energy spectrum decreased more rapidly than predicted because of attenuation of the turbulent velocity variations caused by the relatively large size of the current meter. The average variance for the field of turbulence was 55.6 sq cm - sq sec plus or minus 25.0 (standard error), and the average rate of energy dissipation by viscosity was estimated using the Kolmogoroff hypothesis as 0.84 sq cm - cu sec. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1968
Accession Number
AD0676308

Entities

People

  • Alan T. Massey

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Attenuation
  • Composite Materials
  • Computers
  • Digital Computers
  • Dissipation
  • Impellers
  • Measurement
  • Spectra
  • Standards
  • Tidal Currents
  • Turbulence
  • Viscosity

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Oceanography.
  • Pulsed Power and Plasma Physics.