Principal Length Scales in Second-Order Closure Models for Canopy Turbulence

Principal Length Scales in Second-Order Closure Models for Canopy Turbulence Triaxial sonic anemometer velocity measurements vertically arrayed at six levels within and above a pine forest were used to examine the performance of two second-order closure models put forth by Wilson and Shaw and by Wilson. Based on these measurements, it was demonstrated that Wilson’’s model reproduced the longitudinal velocity standard deviation σσ u better than did Wilson and Shaw’’s model. However, Wilson and Shaw’’s model reproduced the measured mean velocity ⟨⟨ u ⟩⟩ near the forest––atmosphere interface better than Wilson’’s model did. The primary mechanisms responsible for discrepancies between modeled and measured ⟨⟨ u ⟩⟩ and σσ u profiles were investigated. The conceptual formulations of these two closure models differ in the characteristic length scales and timescales used in the closure parameterizations of the mean turbulent kinetic energy dissipation rate term, the pressure––strain rate term, and the flux-transport term. These characteristic length scales were computed and compared with measured integral length scales inside the canopy. A discussion on how these length scales compare with the mixing layer analogy also is presented. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Applied Meteorology American Meteorological Society

Principal Length Scales in Second-Order Closure Models for Canopy Turbulence

Loading next page...
 
/lp/american-meteorological-society/principal-length-scales-in-second-order-closure-models-for-canopy-znUYY28wae
Publisher
American Meteorological Society
Copyright
Copyright © 1998 American Meteorological Society
ISSN
1520-0450
DOI
10.1175/1520-0450(1999)038<1631:PLSISO>2.0.CO;2
Publisher site
See Article on Publisher Site

Abstract

Triaxial sonic anemometer velocity measurements vertically arrayed at six levels within and above a pine forest were used to examine the performance of two second-order closure models put forth by Wilson and Shaw and by Wilson. Based on these measurements, it was demonstrated that Wilson’’s model reproduced the longitudinal velocity standard deviation σσ u better than did Wilson and Shaw’’s model. However, Wilson and Shaw’’s model reproduced the measured mean velocity ⟨⟨ u ⟩⟩ near the forest––atmosphere interface better than Wilson’’s model did. The primary mechanisms responsible for discrepancies between modeled and measured ⟨⟨ u ⟩⟩ and σσ u profiles were investigated. The conceptual formulations of these two closure models differ in the characteristic length scales and timescales used in the closure parameterizations of the mean turbulent kinetic energy dissipation rate term, the pressure––strain rate term, and the flux-transport term. These characteristic length scales were computed and compared with measured integral length scales inside the canopy. A discussion on how these length scales compare with the mixing layer analogy also is presented.

Journal

Journal of Applied MeteorologyAmerican Meteorological Society

Published: May 26, 1998

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off