Basic Research Needs for Clean and Efficient Combustion of 21 Century Transportation Fuels

The next generation of clean, fuel-flexible and efficient engines will operate at pressuresconsiderably higher than those commonly seen in engines today. At these pressures many of thefundamental assumptions underlying present combustion modeling become invalid. Basicresearch is needed to characterize the physical properties and chemical oxidation mechanisms ofcurrent and future transportation fuels at high pressures in order to understand reaction initiationand propagation under these conditions. Fundamental investigations of transport and flowphenomena at high pressure, and their coupling to chemical reactivity, will be essential indescribing these advanced engines. A thorough fundamental understanding of the chemistry andphysics of new fuels in high pressure regimes will require new developments in experimental,theoretical and numerical techniques. The ability to predict fuel/species properties, reaction rates,and ignition behavior is crucial for developing clean and efficient combustion engines.