Modeling the Dispersion of Vapor and Aerosol Particulates in the Atmospheric Boundary Layer

Abstract

The goal of this project is to improve our scientific understanding of dispersion issues over complex terrain and publish results in scientific journals. Three scientific articles and one student's Master thesis are under preparation based on the results supported by this project. The first paper, entitled "The role of advection of fluxes on modeling dispersion in convective boundary layers", is aimed at examining the importance of the advection terms for dispersion in a convective boundary layer. An Eulerian three-dimensional higher-order closure dispersion model is presented. The model uses mean wind and turbulence values from a second order atmospheric boundary layer model. The dispersion model is validated against results from tank and field experiments and compared to results from Lagrangian dispersion models. The results show good agreement with experiment and Lagrangian modeling results for point source dispersion in a convective boundary layer. Sensitivity studies of the model helped to identify the roles that advection and horizontal transport terms in the equations for the fluxes play in simulating the essential features of pollutant dispersion. The results from the sensitivity tests show that the famous features of dispersion from a point source in the convective boundary layer - with an ascending plume during ground level release and descending for a lifted point source - is caused by the advection term in the equation for the vertical flux. Furthermore, it is shown that there is a tendency for the plume to split horizontally, which is also caused by the advection term in horizontal fluxes.

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Document Details

Document Type
Technical Report
Publication Date
May 17, 2001
Accession Number
ADA390236

Entities

People

  • Darko Koračin
  • Leif Enger
  • Steven K. Chai

Organizations

  • University of Nevada, Reno

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Pollution
  • Atmospheric Motion
  • Atmospheric Sciences
  • Boundaries
  • Boundary Layer
  • Coordinate Systems
  • Grids
  • Ground Level
  • Layers
  • Measurement
  • Meteorology
  • Particles
  • Stratified Fluids
  • Three Dimensional
  • Turbulence
  • Two Dimensional
  • Urban Areas

Fields of Study

  • Environmental science

Readers

  • Aerosol Science/Aerosol Physics
  • Computational Modeling and Simulation
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers