Abstract
Urban transport plays an important role in city development and is one of the major sources of environmental pollution. With a view to understand the relationship between the vehicle emissions and traffic control measures, this paper intends to evaluate the relationship between traffic flow and vehicle emissions using the advanced portable emission measurement system, OEM-2100. Real world on-road data collection of emissions for NOx HC, CO and C02 along with engine parameters such as speed was collected and evaluated during acceleration, deceleration, cruising, and idling under dynamic urban traffic conditions in Delhi. The relationship between vehicle emissions and a commonly used traffic measure, control delay, was investigated. Results showed that emissions were episodic in nature and high emissions rates occurred during acceleration, while vehicle emissions were low when the vehicle was idling. Further emission rates of NOx, HC, CO, and CO2 during delay events were significantly higher than during non-delay events.