Observed downwash concentrations compared to ISCST predictions in urban core

Journal Article · Sun Jan 01 04:00:00 EST 1995 · Journal of Environmental Engineering (New York); (United States)

DOI:https://doi.org/10.1061/(ASCE)0733-9372(1995)121:1(16)· OSTI ID:6654925

Thistle, H W ^[1]; Murray, D R; Ratte, M R ^[2]; Carroll, M R ^[3]

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1. Forest Service, Missoula, MT (United States)
2. TRC Environmental Corp., Windsor, CT (United States)
3. Minneapolis Energy Center, MN (United States)

An atmospheric tracer (SF[sub 6]) was released from an industrial stack in an urban core during nocturnal neutral to stable atmospheric conditions in an effort to determine the dispersive characteristics and the atmospheric transport of stack effluent under these conditions. Tracer concentration data are compared to predictions made by the Environmental Protection Agency's Industrial Source Complex Short Term (ISCST) model. ISCST is the regulatory air-pollution model typically recommended in situations where structure-induced plume downwash is a possibility. Under the meteorological conditions and stack parameters sampled in the present study, the downwash algorithm causes the ISCST model to overpredict surface concentrations below 3.5 m/s or below a wind speed/exit velocity (u/V[sub e]) ratio of 0.25. Model performance was better in neutral than in stable atmospheric conditions. The stack effluent temperature was >450 K, and the model overprediction may be due in part to the treatment of thermal buoyancy in the model treatment of building wake downwash.

• OSTI ID: 6654925
• Journal Information: Journal of Environmental Engineering (New York); (United States), Journal Name: Journal of Environmental Engineering (New York); (United States) Vol. 121:1; ISSN 0733-9372; ISSN JOEEDU
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
AIR POLLUTION
CHEMICAL EFFLUENTS
CHEMICAL WASTES
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL TRANSPORT
FORECASTING
MANAGEMENT
MASS TRANSFER
MATHEMATICAL MODELS
NONRADIOACTIVE WASTES
POLLUTION
PRECIPITATION SCAVENGING
SEPARATION PROCESSES
STACK DISPOSAL
URBAN AREAS
WASHOUT
WASTE DISPOSAL
WASTE MANAGEMENT
WASTES