Assessment of exhaust emissions from vehicles in real traffic conditions

Abstract

Every year increase the number vehicle on the road. By 2015 the number of cars on the world was about 1.1 billion. This means that for one car there was 6.5 inhabitants. This number all the time is to increase. It is estimated by 2025 it will exceed 1.5 billion vehicles, and in 2040 it will be already 2 billion. In this case the growth in the global vehicle number and environmental issues requires to reducing the exhaust emissions. The main problem is exhaust emission of vehicles in the city centres but not only, also in extra - urban conditions. Therefore, the focus is on reducing the number of vehicles with significant exhaust emissions and introducing vehicles using alternative fuels. The aim of the article is to present differences in emissions of exhaust gas pollutants using CNG and conventional fuels, from heavy and light vehicles in real traffic conditions. CNG is considered as an alternative fuel. In Poland is during operation relatively large fleet of vehicles with CNG engines, including buses and passenger cars. An in-depth knowledge of the emissivity of such vehicles is a very important issue. The paper presents too, tests under real traffic conditions two city buses that meet the Euro VI emission standards. Diesel engine of the first bus, was fuelled by diesel oil. Spark ignition engine, of the second bus, was fuelled CNG. Tests buses were conducted in real traffic conditions using PEMS devices. The article presents the comparative results of exhaust emission of passenger car with engine fuelled petrol or CNG, during tests D1 and D2 on the chassis dynamometer, tests registered earlier in real traffic conditions. Test D1 reflects urban traffic conditions while D2 test extra - urban conditions.