Diffusion and Ground Deposition of 100 Micron Particles from a Point at a Height of 92 Metres.

Abstract

The results of a series of field trials on the diffusion and ground deposition of 100 micron glass microspheres from a continuous point source at a height of 92 metres are discussed. The observed crosswind integrated deposit density as a function of distance from the source was used to test two prediction models. One of these models employs appropriately averaged standard deviations of vertical turbulence as the main parameter of atmospheric diffusion. The other is the steady state K-Theory diffusion model with a coefficient of eddy diffusivity which varies with height. In general, there was reasonably good agreement between the observed and predicted crosswind integrated deposit density as a function of distance, for the sloping plume model. However, the K-Theory model predicts a peak deposit much lower than observed and a more gradual decrease in the deposit density than observed.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1980
Accession Number
ADA110078

Entities

People

  • Oliver K. Johnson

Organizations

  • Defence Research and Development Canada

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Agreements
  • Boundary Layer
  • Coefficients
  • Crosswinds
  • Diffusion
  • Diffusivity
  • Equations
  • Materials
  • Microspheres
  • Particle Size
  • Particles
  • Standards
  • Steady State
  • Travel Time
  • Turbulence
  • Wind

Readers

  • Aerosol Science/Aerosol Physics
  • Mathematics or Statistics
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers