Abstract
KEYWORDS – exhaust emissions, Real Driving Emissions, conformity factors, passenger cars, topography
ABSTRACT – The paper presents further data related to the results of exhaust emissions investigations under actual traffic conditions (RDE – Real Driving Emissions). The tests were carried out under Polish conditions and were based on the PEMS equipment (Portable Emission Measurement System). Following the obtained results, exhaust emissions conformity factors (CF) were developed, characterized as multiples of the increase/decrease of the exhaust emissions during road tests against the emission standards (emission category) of a tested object. Based on the obtained information, the authors proposed RDE procedures for gasoline and diesel vehicles. In terms of passenger vehicles, the paper presents the results of investigations on the exhaust emissions under varied topographic conditions. The authors have proven that topography has a major impact on emissions and have determined the influence of road grade on the road exhaust emissions (gasoline and diesel engines). The new procedure of vehicles certification for exhaust emissions includes their work under real traffic conditions. Determination of the conformity factors of exhaust emissions is a complex issue and must include additional parameters occurring in the RDE studies such as topography. Development of conformity factors for different vehicle groups is crucial, however, it involves an individual approach. Characteristic operating conditions of vehicles in each group and a variety of external factors affecting on vehicles significantly complicate this issue.