Gasoline and LPG Vehicle Emission Factors in a Road Test

In order to measure the concentration of toxic compounds a mobile analyzer for toxic tests SEMTECH DS by SENSORS Inc. was used. In the study the results of the vehicle emission tests in the road conditions were presented as this was the only way to obtain the information on real vehicle emissions. They include information on the emissivity of the vehicles in operation and deal with the real conditions of the vehicle motion. Reliable measurement results were obtained which were verified in simulated conditions on a chassis test bed. The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the harmful compound emissions. The dynamic engine properties were indirectly taken into account using all the speed range and the range of acceleration calculated for the city traffic in order to prepare a matrix of emission intensity. The data used were averaged within each speed and acceleration range, which generated a characteristics of engine operation in each range and a characteristics of the emission matrices of each harmful compound. The largest share of engine operation in the studied traffic conditions was obtained for the minimum and medium speeds and zero vehicle acceleration. The obtained data enabled to define the vehicle emission factor which can be used to classify fleets of vehicles in relation to toxic compounds emissions that differ e.g. in production date, i.e. limits of exhaust emissions, mileage of vehicles or operation conditions.