Combustion and ignition chemistry in internal combustion engines

摘要

The world relies heavily on internal combustion (IC) engines for transportation, commerce and power generation, and this consumes vast quantities of fuel. Thus, there is much interest in increased fuel efficiency, which has stimulated research in advanced engine combustion concepts due to their higher operating efficiencies when compared with conventional engines. In particular, low-temperature combustion (LTC) strategies, including homogeneous charge compression ignition (HCCI) and its variants, have attracted much interest, as seen, for example, in recent International Journal of Engine Research (IJER) Special Issues. In these engines, the combustion and ignition chemistry of the fuel play a crucial role. This introduces significant challenges for engine control, since the thermodynamic and chemical state of the fuel-air mixture determines the combustion phasing, rather than the fuel injection or spark timing, as in diesel and spark-ignition gasoline engines, respectively. Thus, real-world variations in intake temperature, pressure and gas composition (e.g. exhaust gas recirculation (EGR)), as seen during cold-start or engine transients, can lead to lack of engine control, and complex control systems are required. This introduces additional cost and the need for reliable sensors, such as in-cylinder pressure transducers, for feedback control.