Fluctuation Spectrum and Velocity Structure Function.

Abstract

An equation relating the fluctuation spectrum to the distribution of radial velocity differences of the scatterers, and the pulse volume illumination function is derived. Assuming that the radial velocity differences are due only to turbulence, the particles follow the air motions faithfully, the turbulence is homogeneous, and the reflectivity is constant, then it is shown that the variance of the fluctuation spectrum is a weighted average of the turbulence structure function, the weighting function being completely determined by the pulse volume Illumination function. Various methods of estimating the structure function from measurements of the fluctuation spectrum variance are discussed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1974
Accession Number
AD0775533

Entities

People

  • Jaroslav Sychra

Organizations

  • University of Chicago

Tags

DTIC Thesaurus Topics

  • Equations
  • Illumination
  • Measurement
  • Particles
  • Physical Properties
  • Radial Velocity
  • Reflectivity
  • Spectra
  • Turbulence
  • Weighting Functions

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Approximation Theory.
  • Fluid Dynamics.