Search Results

Mathematical modelling has become an essential tool in the design of modern catalytic systems. Emissions legislation is becoming increasingly stringent, and so mathematical models of aftertreatment systems must become more accurate in order to provide confidence that a catalyst will convert pollutants over the required range of conditions. Automotive catalytic converter models contain several sub-models that represent processes such as mass and heat transfer, and the rates at which the reactions proceed on the surface of the precious metal. Of these sub-models, the prediction of the surface reaction rates is by far the most challenging due to the complexity of the reaction system and the large number of gas species involved.

Particulate emissions, especially ultra-fine particulates, from diesel vehicles constitute the major traffic related environment and health-problem in larger cities today. Particulate filters are a promising solution to this problem. The Danish Road Safety and Transport Agency, in cooperation with the Municipality of Odense, has initiated a large-scale project with the objective to mount filters on some 125 heavy-duty vehicles in daily operation in Odense, to obtain operating experiences and environmental data and to demonstrate the technology.

The aim of the project was to demonstrate and evaluate the feasibility of DME (Dimethyl Ether) fuelled buses, through laboratory and field tests. The performance and emission targets of the HD DME engine has been successfully demonstrated and the bus has been converted to accommodate the DME engine and the fuel tank system. Two DME filling stations have been build. Additives for DME lubrication and odor have been selected. A Life Cycle Analysis (LCA) has been made under International Energy Agency (IEA) auspices by some of the project participants. The project has added valuable information, to the over all development of DME fueled vehicles. The strong arguments for DME as a major future fuel are briefly covered including production costs, emissions and feed stock diversity.