Analytical approach to estimate pollutant concentrations from a tunnel portal exit plume
- Parsons Brinckerhoff Inc., New York, NY (United States)
This paper discusses an approach for estimating pollutant concentrations in a portal exhaust plume using the USEPA Industrial Source Complex (ISC) Gaussian dispersion model. This approach incorporates procedures developed using wind-tunnel data generated for the Central Artery/Tunnel Project in Boston, Massachusetts. No mathematical model exists that precisely describes the configuration of a portal exhaust plume. It is known, however, that the dimensions of the plume depend on several factors. These include the speed of the vehicles moving in the tunnel, atmospheric wind speed and direction, the topography of the area immediately surrounding the tunnel portal, the type of tunnel (i.e., whether it is one-way or two-way), the geometry of the portal (i.e., its height and physical configuration) and the type of ventilation system used in the tunnel (i.e., either longitudinal or transverse). This analytical method had been used for several tunnel project in the United States and Far East. In the applications of the discussed modeling procedure, the portal plume is represented with a series of rectangular shape volume sources downstream of the portal. The actual size of the plume is determined on a case-by-case basis. Inputs to the modeling procedure include meteorological data and estimated mobile source emissions. Contributions to the ambient air quality levels from the portal plume are combined with contributions from other relevant sources including surface traffic downstream the portal.
- OSTI ID:
- 351682
- Report Number(s):
- CONF-970677--
- Country of Publication:
- United States
- Language:
- English
Similar Records
A methodology to control air quality levels near the tunnel portals and optimize ventilation system design
Accuracy of wind tunnel modeling of buoyant plume rise around buildings