The soot formation and in-cylinder soot oxidation in an optically accessible DISI-engine is analyzed for gasoline-ethanol and -butanol mixtures. The volumetric extinction measurement technique used is capable of determining quantitative soot volume fractions and in-cylinder soot oxidation at low gas and soot particle temperatures. Toliso, a fuel mixture containing isooctane and toluene (65 vol% isooctane and 35 vol% toluene) was utilized as a surrogate gasoline fuel. The EGR-dependence (EGR-exhaust gas recirculation) on soot formation and -oxidation of the fuels was studied at part load operation. The studied operating point is characterized by an early injection timing leading to distinct piston wetting and a sooting pool-fire. The measurements without EGR showed a low soot formation for Toliso, while EGR leads to higher soot formation. E20 and B20 showed a strong sooting behaviour without EGR. An EGR increase reduced the soot formation for E20 and B20. It can be concluded that the physical fuel properties determine the spray formation and piston wetting. The fuel dependent evaporation of the liquid wall film as well as local mixing conditions play a major role on soot formation and oxidation.

对于汽油-乙醇和-丁醇混合物，分析了光学可访问的DISI发动机中的烟灰形成和缸内烟灰氧化。所使用的体积消光测量技术能够确定低烟气和烟灰颗粒温度下烟灰体积分数的定量和缸内烟灰氧化。含有异辛烷和甲苯（65体积％异辛烷和35体积％甲苯）的混合燃料Toliso被用作替代汽油燃料。在部分负荷运行下，研究了燃料对碳烟形成和氧化的EGR依赖性（EGR废气再循环）。所研究的工作点的特点是提前喷射正时，导致明显的活塞润湿和积灰积炭。不使用EGR的测量结果显示Toliso的烟灰形成较低，而EGR导致的烟灰形成较高。E20和B20在没有EGR的情况下显示出很强的烟ot行为。EGR的增加减少了E20和B20的烟灰形成。可以得出结论，物理燃料特性决定了喷雾的形成和活塞的润湿。取决于燃料的液壁膜的蒸发以及局部混合条件对烟灰的形成和氧化起着重要作用。