| Title | Modifications of highway air pollution models for complex geometries, volume II : wind tunnel test program. |
|---|---|
| Record ID | 46520 |
| Corporate Creator | Technology Integration and Development Group, Inc.; Boston University; Sigma Research Corp. |
| Corporate Contributor |
United States. Federal Highway Administration; United States. Department of Transportation. Federal Aviation Administration |
| Publisher | Turner-Fairbank Highway Research Center |
| Publication Date | 20020900 |
| Language | English |
| Abstract | This is volume I1 of a two-volume report of a study to increase the scope and clarity of air pollution models for depressed highway and street canyon sites. It presents the atmospheric wind tunnel program conducted to increase the data base and improves physical concepts of pertinent movements and mixing of air and its contaminants. Wind tunnel measurements are less costly than field measurements and are sensitive to controlled input variables. The f~swti nd tunnel operations assured geometric, vortex structure, and upstream flow similarity and correct building wake and moving vehicle effects. Tracer gases from point, line, and moving vehicle sources were used appropriately. For wind tunnel models of depressed roads or street canyons hot-wire anemometer velocity and turbulence, pressure distribution and receptor point concentration measurements were made. Using a selected standard road model which had two dimensions and a width/ height (W/H) ratio of one effects of wind angle, local source location, added upwind cuts, vehicle speed, ambient wind speed, and the presence of upwind wall canopy were observed. Other two-dimensional tests involved changing the w/H ratios from 0.25 to 6.0, sloping the walls, slotted walls, walls of unequal heights, and curved roads. Three dimensional tests included end effects, intersections, and an added taller structure along one side of the road. Test results gave qualitative evaluations, concise tables, graphic illustrations, and qualitative concepts of wind flows and dispersion. Some findings include: (1) Wind flows and air pollution impacts are affected by W/H ratio, road curvature, and slope of walls, vehicle movements, and source locations. Slotted buildings upwind reduce impacts. (2) Air contaminant concentrations are reduced near intersections due to vertical vortices at corners (3) Simulations of five field sites by wind tunnel tests were satisfactory. Volume I is publication FHWA-RD-02-036, " Data Analyses and Model Developmenty |
| Rosap ID | dot:25304 |
| Rosap URL | https://rosap.ntl.bts.gov/view/dot/25304 |
| General Subjects | Air pollution; Street canyons; Highway cut; Urban dispersion models; Wind tunnel; Turbulence |
| Geographical Coverage |
Minnesota; New York; Texas; Washington |
| TRIS Online Accession No |
932051 |
| Contract Number | DTFH61-84-C-00104 |
| Report Number | FHWA-RD-02-037; R 8806-002-RD |
| Resource type | Tech Report |
| URL | https://ntlrepository.blob.core.windows.net/lib/46000/46500/46520/FHWA-RD-02-037.pdf |
| Format | |
| Database | NTL Digital Repository |