INVESTIGATION OF ATMOSPHERIC DIFFUSION PROCESSES BY MEANS OF EXPERIMENTAL, ANALYTICAL, AND NUMERICAL TECHNIQUES

Abstract

The paper concerns an investigation of the atmospheric diffusion processes by means of experimental, analytical, and numerical methods. Experimental momentum transfer and heat transfer analyses are presented. Shear stresses in the surface layer are measured directly by means of a shear meter; momentum eddy diffusivities and drag coefficients over flat ground are determined from shear stress and wind velocity data. Convective heat transfer rates in the surface layer are measured indirectly by means of a heat flow meter and a radiometer; convective conductances are determined from the convective heat flow and air temperature data. Two new, analytical, periodic, convective heat flow solutions for the atmospheric system are derived. One solution pertains to an eddy diffusion system in which the boundary temperature varies sinusoidally with time and the eddy diffusivity varies sinusoidally with time but is independent of height. The other solution pertains to an eddy diffusion system in which the boundary temperature varies sinusoidally with time and the eddy diffusivity varies sinusoidally with time and linearly with height. A simple heat-momentum transfer analogy for the surface layer was developed which relates some of the pertinent heat and momentum transfer variables in the atmospheric diffusion system.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1950
Accession Number
AD0492301

Entities

People

  • H. F. Poppendiek
  • J. E. Vehrencamp

Organizations

  • University of California, Los Angeles

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Engineering
  • Fluid Mechanics
  • Heat Balance
  • Heat Energy
  • Heat Transfer
  • Heat Transmission
  • Lapse Rate
  • Latent Heat
  • Mass Transfer
  • Measurement
  • Meteorology
  • Momentum Transfer
  • Steady State
  • Turbulence
  • Water Vapor
  • Wind Velocity

Fields of Study

  • Environmental science

Readers

  • Combustion and Flow Dynamics.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Structural Dynamics.