Turbulent diffusion in the Ekman boundary layer

Conference · Thu Jan 01 04:00:00 EST 1976

OSTI ID:7342862

Paegle, J N; Kao, S K

Numerical models are developed to simulate the dispersion of pollutants emitted from a ground source in the Ekman boundary layer for three different boundary conditions. They are reflecting upper and lower boundaries, an open upper boundary and a reflecting lower boundary, and an open upper boundary and a total absorption lower boundary. It is shown that the maximum concentration generally shifts anticyclonically (toward the right in the Northern Hemisphere, left in the Southern Hemisphere) with increasing height as a consequence of the effects of the Coriolis and frictional forces in the planetary boundary layer. In the case of reflecting upper and lower boundaries, concentration tends to be uniformly distributed along the vertical as the radial distance increases. In the case of an open upper boundary and a reflecting lower boundary, at all points the concentration appears to be lower than that in the previous case, because of the lack of the upper boundary which allows the removal of pollutants vertically. In the case of an open upper boundary and a total absorption lower boundary, the distribution of concentration appears to be different from the two previous cases in that the maximum concentration occurs at higher levels. For the two cases with open upper boundaries, the pollutants stay at lower levels at large angles, while they are found at higher levels at directions close to that of the geostrophic wind above.

• Research Organization: Utah Univ., Salt Lake City (USA)
• OSTI ID: 7342862
• Report Number(s): COO-2455-11; CONF-761003-17
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
BOUNDARY CONDITIONS
BOUNDARY LAYERS
CORIOLIS FORCE
DIFFUSION
ECOLOGICAL CONCENTRATION
LAYERS
MASS TRANSFER
MATHEMATICAL MODELS
POLLUTION
TURBULENCE
WIND