VOC Emissions and OFP Assessment for Two Real World Urban Driving Cycles using a EURO 2 SI Car 2008-01-1303
A FTIR in-vehicle on-road emission measurement system was installed in a EURO2 emissions compliant SI (Spark Ignition) car to investigate exhaust Volatile Organic Compounds (VOC) emissions and Ozone Formation Potential (OFP) under different urban traffic conditions. The real time fuel consumption and vehicle traveling speed were measured and logged. The temperatures were measured along the exhaust pipe so as to monitor the thermal characteristics and efficiency of the catalyst. Two real world driving cycles were developed with different traffic conditions. One (West Park Loop cycle) was located in a quiet area with few traffic interference and the other one (Hyde Park Loop cycle) was in a busy area with more traffic variations. The test car was pre-warmed before each test to eliminate cold start effect.
The driving parameters were analyzed for two real world cycles. The WPL cycle had higher acceleration rate, longer acceleration mode and less steady speed driving mode and thus harsher than the HPL cycle. The 52 volatile organic compounds (VOCs), including benzene, toluene and 1,3butadiene VOC emissions were measured. OFP was evaluated using Maximum Incremental Reactivity (MIR). The results showed higher VOC emissions and OFP for the WPL cycle, indicating that an isolated driving cycle produced greater emissions because of free accelerations and more change on driving mode. The research helped to understand traffic emission profiles in urban areas. The data of this research can be used for prediction of VOC emissions and OFP in cities.