Project. Emissions modeling    Partially Completed

Principal investigator. Dr. Hesham Rakha, Virginia Tech, 540-231-1505, rakha@ctr.vt.edu

External contacts. none

Project objective. To model vehicle emissions at a more precise level than has been done before, taking into account acceleration and idling.

Project abstract. Contributing to the effort to achieve the air quality goals set in the Clean Air Act Amendments (CAAA) of 1990 and ISTEA, ITS applications attempt to relieve traffic congestion, reduce vehicle delay, reduce vehicle fuel consumption, and reduce vehicle emissions.

The accurate modeling and estimation of vehicle exhaust emissions are very important for the evaluation of ITS systems; however, current state-of-the-practice emission models (MOBILE5, MOBILE6 and EMFAC) are insensitive to a vehicle's modal events, such as acceleration/ deceleration, cruise speed, and idling. Consequently, these models are not suitable for evaluating the environmental impacts of ITS.

The proposed research effort will extend and develop microscopic energy and emission models developed as part of the Metropolitan Model Deployment Initiative. The models will be developed using second-by-second energy and emission data that were collected by EPA and including the vehicle's instantaneous speed and acceleration and its corresponding Hydrocarbon (HC), Carbon Monoxide (CO), Carbon Dioxide (CO₂), and Oxides of Nitrogen (NO_x) emissions for a total of 100 vehicles. The models will be validated by collecting on-board tailpipe vehicle emissions as vehicles travel in the field.

Tasks.
1) Develop microscopic energy and emission models for Light Duty Vehicles (LDVs) under hot stabilized conditions.
2) Develop models accounting for cold starts and for high emitting vehicles.

Milestones. The first set of models will be completed by June 30, 2001; the second, by June 30, 2002.

Student involvement. none

Budget.   $100,000

Relationship to other research projects. No immediate relationships.

Technology transfer. Publication in professional journals.

Potential benefits. Increased capacity by planners to meet air quality goals set in the Clean Air Act Amendments of 1990.

TRB keywords: ITS, models, environment