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This paper describes the demands and potentials of current and future gasoline combustion systems regarding the fuels gasoline, natural gas, and Hydrogen. At first, fuel specifications that are crucial for the spark ignition process are compared. These are compared with the requirements of the combustion system. Potentials for the compensation of power loss, efficiency improvement and emission reduction using alternative fuels are discussed taking into account fuel-specific properties. While full load drawbacks with natural gas compared with gasoline can be reduced to less than 5% by combustion system tuning, Hydrogen operation with port injection leads to reductions of about 25 to 30%. These drawbacks can be compensated with boosting where both methane and Hydrogen are qualified due to their burning characteristics. Compared with λ=1 operation especially Hydrogen offers efficiency benefits of up to 30% in a wide mapping range due to quality control.

This paper focuses on start-up technology for fuel processing systems with special emphasis on gasoline fueled burners. Initially two different fuel processing systems, an autothermal reformer with preferential oxidation and a steam reformer with membrane, are introduced and their possible starting strategies are discussed. Energy consumption for preheating up to light-off temperature and the start-up time is estimated. Subsequently electrical preheating is compared with start-up burners and the different types of heat generation are rated with respect to the requirements on start-up systems. Preheating power for fuel cell propulsion systems necessarily reaches up to the magnitude of the electrical fuel cell power output. A gasoline fueled burner with thermal combustion has been build-up, which covers the required preheating power.

A Diesel spray and combustion model has been connected to the CFD-code StarCD. The paper provides an overview of the submodels implemented, which account for liquid core atomization, droplet secondary break-up, droplet collision, impingement, turbulent dispersion and evaporation. Auto-ignition and combustion is described by the Representative Interactive Flamelet (RIF)-model. This concept allows to separate the fluid dynamics from the chemical processes with their significantly smaller timescales, and enables to account for a sufficiently large number of chemical species and reactions in order to predict pollutant formation such as NOx and soot. The CFD-predictions are extensively compared to experimental data. Spray model validation cases focus on the distribution of droplet sizes, velocities and fuel vapor in free and impinging sprays.