Aufbau und Einsatz eines on-board Messsystems zur Untersuchung der Abgaszusammensetzung von Fahrzeugen betrieben mit konventionellen und alternativen Kraftstoffen

RWTH Publications (RWTH Aachen)

Abstract

The central theme of this thesis is the experimental analysis of the combustion-related emissions in the gas phase of conventional as well as alternative diesel- and gasoline-type fuels by conducting on-road exhaust gas analysis in real-time under real operating conditions using a developed Portable Emissions Measurement System (PEMS). First, both the air-chemical processes as well as the sources of pollutants and condition-based emissions are presented. A PEMS will then be developed, considering the existing exhaust gas measurement methods, in order to carry out a comparative air-chemical assessment with regard to their impact on local air quality and their ability to form photooxidants. The developed PEMS represents an extension of the limited emissions of the European emission standard Euro-6 and continuously measures CO, CO2, O2, NO, NO2, N2O, HC in real-time as well as discontinuous measures differentiated hydrocarbons offline. The usage of Biodiesel FAME UCOME under warm operating conditions shows the greatest reduction potential compared to conventional diesel fuel with a reduction in NOx of 14%, in N2O of 41% and in CO of 25%. The gasoline fuels show a differentiated representation regarding the emission reduction potentials under warm operating conditions. Alkylate-Petrol 4T achieves a 72% reduction in NOx but an increase in HC emissions by a factor of 4.7. Under cold start conditions Biodiesel FAME RME achieves the comparatively lowest NOx emission share of 12% among the diesel-type fuels and Super E10 achieves the comparatively lowest NOx emission share with 47% among the gasoline-type fuels. Heating effects of the catalytic converter lead to an increase in HC emissions by a factor of up to eleven. Model studies on the cumulative ozone formation with fuel-dependent emissions lead to a 19% reduction in ozone formation during cold starts when using alternative fuels for gasoline cars and by 5% for diesel cars. In contrast, the results of the intrinsic ozone formation and the VOC/NOx dependent ozone formation of gasoline-type fuels are higher than the ozone formation potential of diesel-type fuels. Therefore, the VOC/NOx ratio significantly influences the ability of the ozone formation potential. A nationwide introduction of Alkylate-Petrol 4T will increase the N2O climate impact by a factor of two compared to Super E5. However, this corresponds to a change in CO2 climate impact of less than 2%. By using existing traffic integration forecasts, the analysis of the future scenarios has shown that the NOx emissions of the passenger car fleet can be reduced by 53% in 2030 and by 88% in 2050 if alternative fuels are used. Assuming a falling traffic volume of vehicles with internal combustion engines, the utilization of alternative drop-in fuels such as Biodiesel FAME UCOME in Euro-5 diesel vehicles will reduce ozone formation from traffic-related emissions by 1% compared to the utilization of conventional diesel fuel in 2030. Likewise, a reduction in ozone formation of 24% in 2021, 22% in 2030 and 12% in 2050 was calculated, when using Alkylate-Petrol 4T compared to the use of conventional Super E5.

Authors 1

1. Valentin Polinowski corresponding Aachen

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen