Analysis of Emission Characteristics for In-Use Diesel Vehicles in Xi'an
To provide technical support for the development and emission control of in-use diesel vehicles in Xi’an and other typical second-tier cities, the emission characteristics of particulate matter emitted from in-use vehicles especially high emission vehicles were analyzed by using the Lug- down mode test data of diesel vehicles in Xi'an. Further, the influences of vehicle control technology level, mileage and vehicle age on vehicle emissions were evaluated. When the vehicle mileage is greater than 10 million kilometers, emissions deterioration is obvious; and the same deterioration is observed with the increase of vehicle age. Vehicles with the mileage of 7 million to 8 million kilometers and vehicle age between 4 and 7 years also need to pay much more attentions. China I vehicles have the highest proportion of high emission vehicles, and China III vehicles have the largest number of high emission vehicles.