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在柴油机内,燃料喷射到燃烧室内热的压缩空气中。这样的柴油燃烧过程基本上是不均匀的,并且燃烧室中燃料和空气的混合控制着整个燃烧过程。既然燃料—空气的混合是这样重要,喷射的燃料的分布就对燃烧工况有着很大的影响。这对于直接喷射的柴油机更为确实,因为它们的空气扰动率相对地低。在所有的柴油机中,燃料是在高压下通过小的喷嘴喷进燃烧室的。燃料从喷嘴射出后,形成雾化液体的喷柱。喷柱的穿透、分布和汽化,还有空气的扰动,控制着燃料和空气的混合。喷柱的穿透度在本论文第一部分论述;第二部分叙述了燃料喷柱的汽化度。
In a diesel engine, fuel is injected into hot compressed air in the combustion chamber. Such a diesel combustion process is substantially inhomogeneous, and the mixture of fuel and air in the combustion chamber controls the entire combustion process. Since fuel-air mixing is so important, the distribution of injected fuel has a significant impact on the combustion conditions. This is more true for direct injection diesel engines because their air turbulence rates are relatively low. In all diesel engines, the fuel is injected into the combustion chamber through small nozzles at high pressure. After the fuel is ejected from the nozzle, a spray of atomized liquid is formed. Penetration, distribution and vaporization of the jet, as well as air turbulence, control the mixing of fuel and air. Penetration of the jet is discussed in the first part of the paper; the second part describes the degree of vaporization of the fuel jet.