EMISSION CHARACTERISTICS OF DIFFERENT COMBUSTION ENGINES IN THE CITY,ON RURAL ROADS AND ON HIGHWAYS

For passenger cars the different emission rates for CO, HC, NO(x), and particles are described for operation in cities, on rural roads and o n highways. Since there are great differences a distinction is made fo r the following combustion types: gasoline two-stroke and four-stroke engines without catalyst, gasoline engines with catalyst, with and wit hout an oxygen sensor, diesel engines with and without an oxidation ca talyst. The operation in cities is defined through different driving c ycles, e.g. the European and US-City driving cycle and TUV Rheinland u rban cycles M3 and M4. The extra urban traffic is defined with intra- and extrapolation of another TUV Rheinland cycle M2 with an average sp eed of 60 km/h and the constant speed of 100 km/h as well as the new E uropean extra urban driving cycle. The emissions at 100 are multiplied by 30% to take into account the intermittent operation. As a result a ranking for each component is given. For CO two-stroke gasoline engin es, four-stroke gasoline engines, gasoline engines with a catalyst wit hout an oxygen sensor, gasoline engines in which the catalyst has an o xygen sensor, diesel engines and diesel engines with an oxidation cata lyst. Two-stroke gasoline engines are by far the main HC-emitter. For HC and NO(x), the diesel engine is a little worse than catalyst equipp ed gasoline engines.Particles are mainly a problem for diesel engines but modem diesel engines have relatively low particle emission rates.