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目前,一些汽车用直喷式柴油机的最重要的发展目标是:降低碳烟、NOx和噪声污染并尽可能提高升功率。燃料的喷射和燃烧室内的流动能够影响燃烧,而为获得较好的燃油雾化,尤其值得推荐采用多个小的喷孔。由此可缩小喷射宽度并在一定的运行状态时减少喷到燃烧室壁的燃油量。整个喷射过程对HOx和噪声的控制最好用泵-喷咀系统实现。通过挤压流动能够有效地形成燃烧室内的涡流。作为形成涡流的特别措施建议在活塞凹坑圆周上制出附加开口。喷射图像时和燃烧室内涡流的变化取决于进气螺旋气道的重新最佳化,而所期待的进气涡流的减小在全负荷提高充气系数并在宽广的转速范围内带来涡流更好的匹配司能性。而所有这些喷射装置和燃烧室的改变必须用提高工艺技术费用来换取。
At present, some of the most important development goals for direct injection diesel engines for automotive use are: to reduce soot, NOx and noise pollution and to maximize lift power. Fuel injection and combustion chamber flow can affect the combustion, and in order to obtain a better fuel atomization, in particular, it is recommended to use multiple small holes. As a result, the injection width can be reduced and the amount of fuel injected to the combustion chamber wall can be reduced during a certain operating state. The entire spray process on the HOx and noise control is best achieved with the pump - nozzle system. The eddy current in the combustion chamber can be efficiently formed by the squeeze flow. As a special measure for eddy currents, it is advisable to make additional openings in the circumference of the piston pit. The variation of the swirl in the injection and in the combustion chamber depends on the re-optimization of the inlet spiral duct, and the expected reduction of the intake swirl at full load increases the air-entrainment coefficient and gives better turbulence over a broad speed range The ability to match the Secretary. All of these injection devices and combustion chamber changes must be made with increased process technology costs.