Increased Diesel Engine Air Utilization Analysis: Closer to StoichiometricCombustion

摘要

Large gains in propulsion system reduction can be achieved by moving closer tostoichiometric combustion in diesel engines. This paper is intended to identify possible fuel injection and combustion strategies to achieve higher diesel engine power density via improved air utilization. The following technology should be addressed for near-term solutions to better air utilization in diesel engines. Utilize high pressure injection equipment that has flexible rate shaping and the smallest possible injector holes. Ideally, fuel injection systems that can control split injections are needed. The appropriate combustion chamber is the quiescent chamber to match the high injection pressures and a shallow combustion bowl. It is necessary to eliminate dead-volumes by moving the top piston ring as close to the crown as possible and reducing the piston-to-cylinder head clearance. If possible, it is advisable to use flush mounted valves and eliminate valve pockets. Increased turbocharger boost would allow smaller engine packaging. Methods to control peak cylinder pressure should be considered. The most promising long-term technology is the Homogeneous Charge Compression Ignition (HCCI) combustion process. Stoichiometric combustion is possible without visible smoke. Further development of this system is necessary for this to be a viable solution.