TURBULENT DIFFUSION OF SMALL PARTICLES.

Abstract

It is the purpose of this project to determine the later diffusivity of single spherical particles in an isotropic turbulent air flow and the corresponding Lagrangian velocity autocorrelation coefficient. The particles are to vary in size, density, and in time constant, and are to have a stable wake. Results of mean flow and turbulence intensity measurements are presented. They show the mean velocity profiles to be flat and the turbulence to be homogeneous in planes perpendicular to the mean flow direction and to decay in the streamwise direction as predicted. The calculation showing what spread in particles size can be tolerated to result in an acceptable error in the correlation coefficient for the small particles is presented. The project room was made ready for the particle detection system. The timing system was matched with the trigger circuits in the flash light sources. The entire control system was set-up. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 20, 1968
Accession Number
AD0833254

Entities

People

  • John L. Lumley
  • William H. Snyder

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Flow
  • Coefficients
  • Control Systems
  • Diffusion
  • Diffusivity
  • Flow
  • Light Sources
  • Particles
  • Trigger Circuits
  • Turbulence
  • Turbulent Diffusion

Fields of Study

  • Physics

Readers

  • Aerosol Science/Aerosol Physics
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Dynamics.