Main Title |
Simple PDF (Probability Distribution Function) Models for Convectively Driven Vertical Diffusion. |
Author |
Zong-Kai, L. ;
Briggs, G. A. ;
|
CORP Author |
Environmental Protection Agency, Research Triangle Park, NC. Atmospheric Sciences Research Lab. ;Nanjing Univ. (China). Dept. of Atmospheric Sciences. |
Publisher |
c1988 |
Year Published |
1988 |
Report Number |
EPA/600/J-88/329; |
Stock Number |
PB89-206692 |
Additional Subjects |
Probability distribution functions ;
Mathematical models ;
Atmospheric diffusion ;
Boundary layer ;
Wind velocity ;
Convection ;
Heat transfer ;
Turbulent flow ;
Aerial surveys ;
Optical radar ;
Comparison ;
Reprints ;
Gaussian plume models ;
Tracer studies
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB89-206692 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
22p |
Abstract |
The mode of vertical velocity in convective boundary layers is usually negative and the probability distribution function (PDF) of w, P(sub w), is rarely symmetric. Consequently, vertical diffusion from elevated sources is usually asymmetric and exhibits a descending mode of concentration, causing higher peak surface concentrations than predicted by Gaussian models. The main concentration (X) effects, the authors argue, can be modeled using simple PDF diffusion models, with tracers responding to P(sub w) at the source height with straight line trajectories and simple reflection at the surface and z(sub i), the mixing depth. The critical element is the choice of P(sub w). The PDF models are compared with diverse selection of atmospheric turbulence measurements. Recent lidar measurements of oil fog plumes are presented that show a large variability. |
Supplementary Notes |
Pub. in Atmospheric Environment, v22 n1 p55-74 1988. Prepared in cooperation with Nanjing Univ. (China). Dept. of Atmospheric Sciences. |
NTIS Title Notes |
Journal article. |
Title Annotations |
Reprint: Simple PDF (Probability Distribution Function) Models for Convectively Driven Vertical Diffusion. |
Category Codes |
55B; 55C |
NTIS Prices |
PC A03/MF A01 |
Primary Description |
600/09 |
Document Type |
NT |
Cataloging Source |
NTIS/MT |
Control Number |
925823405 |
Origin |
NTIS |
Type |
CAT |