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Depressed Roadways

Metadata Updated: November 12, 2020

This data set is associated with the results found in the journal article: Amini et al, 2018. Modeling Dispersion of Emissions from Depressed Roadways. Authors: Seyedmorteza Amini, Faraz Enayati Ahangar, David K. Heist, Steven G. Perry, Akula Venkatram. This paper presents an analysis of data from a wind tunnel study of dispersion of emissions from three depressed roadway configurations; a 6 m deep depressed roadway with vertical sidewalls, a 6 m deep depressed roadway with 30° sloping sidewalls, and a 9 m deep depressed roadway with vertical sidewalls. All these configurations induce complex flow fields, increase turbulence levels, and decrease surface concentrations downwind of the depressed road compared to those of the at-grade configuration. The parameters of flat terrain dispersion models are modified to describe concentrations measured downwind of the depressed roadways. In the first part of the paper, a flat terrain model proposed by van Ulden (1978) is adapted. It turns out that this model with increased initial vertical dispersion and friction velocity is able to explain the observed concentration field. The results also suggest that the vertical concentration profiles of all cases under neutral conditions are best explained by a vertical distribution function with an exponent of 1.3. In the second part of the paper, these modifications are incorporated into a model based on the RLINE line-source dispersion model. While this model can be adapted to yield acceptable estimates of near-surface concentrations (z< 6m) measured in the wind tunnel, the Gaussian vertical distribution in RLINE, with an exponent of 2, cannot describe the concentration at higher elevations. Our findings suggest a simple method to account for depressed highways in models such as RLINE and AERMOD through two parameters that modify vertical plume spread.

This dataset is associated with the following publication: Amini, S., F. Ahangar, D. Heist, S. Perry, and A. Venkatram. Modeling Dispersion of Emissions from Depressed Roadways. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, USA, 186: 189-197, (2018).

Access & Use Information

Public: This dataset is intended for public access and use. License: See this page for license information.

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Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020

Metadata Source

Harvested from EPA ScienceHub

Additional Metadata

Resource Type Dataset
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Publisher U.S. EPA Office of Research and Development (ORD)
Data Last Modified 2018-05-11
Public Access Level public
Bureau Code 020:00
Schema Version
Data Dictionary
Data Dictionary Type application/pdf
Harvest Object Id 8788efe4-a52f-4595-90ca-06f4ff4aeadd
Harvest Source Id 04b59eaf-ae53-4066-93db-80f2ed0df446
Harvest Source Title EPA ScienceHub
Program Code 020:094
Publisher Hierarchy U.S. Government > U.S. Environmental Protection Agency > U.S. EPA Office of Research and Development (ORD)
Related Documents
Source Datajson Identifier True
Source Hash ff821f9f457ba82094813614146da5fd5692bd97
Source Schema Version 1.1

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