Experimental data sets: Top-level page in hierarchy on data sets.
Data set repositories: Lists compilations of data sets.
List of individual data sets: Lists links to information on individual data sets.
Forum for individual data sets: Findings related to data sets can be reported in detail.
Basic information on the data set[edit | edit source]
In 1990 a comprehensive data set on dispersion behind rectangular buildings was assembled in the US EPA wind tunnel, through efforts led by R. Thompson. The data set systematically describes dispersion for a variety of building shapes, stack heights and stack locations. These data were originally used to estimate so-called Building Amplification Factor. However, the potential of the data set extends much beyond this application.
The main published reference to the data set is the paper: Thompson, R. S. (1993): Building Amplification Factors for Sources Near Buildings - A Wind-Tunnel Study. Atmospheric Environment Part A-General Topics 27, 2313-2325.
The experimental database of Thompson includes measurements of ground-level centreline concentration distributions for several different combinations of building shapes, stack heights, and stack location relative to the building. The data set includes around 250 scenarios, where the following parameters vary:
- Building shape: Four building geometries were considered, as well as a baseline scenario without building.
- Stack height: In terms of relative stack height (stack height divided by building height), emphasis was on five values ranging from 0.5 to 3. There are a few scenarios for additional stack height.
- Stack location: The location of the stack varied, so there are scenarios with the stack upwind of the building, on top of the building, and downwind of the building. Altogether 17 stack locations were considered, extending 14 building heights upwind of the building to 12 building heights downwind.
Not all combinations of the parameters were considered, but there are altogether around 250 scenarios. The wind was always perpendicular to the building face.
Essence of experiences with the data set[edit | edit source]
Thompson's data set is very comprehensive, and it deserves to be used much more than it has been in the past.
Availability of the data set and access to validation studies[edit | edit source]
This page is set up by Helge Rørdam Olesen of the National Environmental Research Institute (NERI) in Denmark. Our group has made a study where we used the data to study model performance. We received the data from Steve Perry of the US EPA. The data were made available to us in the form of a large number of ASCII files and a data report by Thompson (1991).
We have rearranged the data sets into a few Excel workbooks with embedded graphs and macros, so the user can vary the stack height or the stack location (using arrow keys), and inspect the resulting changes in concentrations according to both measurements and models. The figure on top is a chart from one of these workbooks.
The Excel workbooks and a lot of other material is available on the web. A page at NERI's web server provides an entry to all of it. A Power Point show provides an easy introduction. Go through the entry page at NERI or use the Direct link to the PowerPoint show.