论文部分内容阅读
改进直喷柴油机的性能,如降低氮氧化合物(NO_x)和颗粒(PM)排放,提高输出功率等,燃油喷注的雾化起着重要作用。为了获得良好的燃油雾化而又不增加燃油喷射压力,有效途径是增加在喷油嘴喷孔中的燃油流速。通过扩大喷孔进口处的圆角被证明是制造具有高燃油流速喷油嘴的非常有效和合适的方法。本文比较了高流速喷油嘴和常用喷油嘴在喷射特性和喷雾特性方面的差别,并且证实了具有高流速的喷油嘴改善了燃油喷注的雾化。本文最后列举了将高流速喷油嘴装在中型、自然吸气直喷柴油机上进行试验的情况。高流速喷油嘴改善了NO_x—PM的综合性能,提高发动机输出功率,因此证明了这是一种改善发动机性能的有效方法。
Improve the performance of direct injection diesel engine, such as reducing nitrogen oxides (NO_x) and particulate (PM) emissions, increase output power, atomization of fuel injection plays an important role. In order to obtain good fuel atomization without increasing the fuel injection pressure, it is an effective way to increase the fuel flow rate in the nozzle orifice. By enlarging the fillet at the orifice entrance has proved to be a very effective and suitable method of making a nozzle with a high fuel flow rate. This article compares the differences in injection and spray characteristics between high-flow and common-use injectors and demonstrates that high-velocity injectors improve atomization of fuel injections. At the end of this article, we list the case where the high-velocity nozzle is mounted on a medium-sized, naturally aspirated, direct-injection diesel engine. High flow rate injectors improve NO_x-PM’s overall performance and increase engine output, thus proving that this is an effective way to improve engine performance.