论文部分内容阅读
本研究涉及共轨直喷式小缸径车用柴油机的光学试验,其目的是研究喷束在活塞顶凹坑壁的撞击点位置对碳烟排放的影响。试验在一台装有共轨喷油器和盆形燃烧室活塞的单缸、4气门柴油机上进行。将传统的活塞加长,活塞顶采用石英材料,为燃烧室提供了第一条光学通路,透明的石英气缸套提供了第二条光路。采用激光诱导激态复合物荧光技术实现液相和汽相燃料的可视化,利用加强型 CCD 摄像机,通过直接光线照射监测记录了燃烧和碳烟排放的图像。同时还用标准烟度计对排气管中的碳烟排放进行了分析。在几种不同的喷油器垂直安装位置下进行的试验表明,喷束在活塞顶凹坑的撞壁位置对碳烟排放影响很大。本研究燃料和燃烧可视化图像的分析表明,这种现象与燃料蒸气在燃烧室中挤气区和活塞顶凹坑的分布有关。
The objective of this study is to study the optical test of common rail direct injection small bore diesel engine. The purpose of this study is to study the influence of the jet on the soot emission at the impact point of the pit wall. The test was carried out on a single-cylinder, 4-valve diesel engine equipped with a common rail injector and a bowl-shaped combustion chamber piston. Extending the traditional piston with a quartz top on the piston top provides the combustion chamber with the first optical pathway and the transparent quartz cylinder liner provides the second light path. Liquid-phase and vapor-phase fuels were visualized using laser-induced excimer fluorescence technology, images of combustion and soot emissions were monitored by direct light exposure using a rugged CCD camera. At the same time, the standard smoke meter was used to analyze the soot emission in the exhaust pipe. Tests carried out at several different injector vertical mounting locations show that the spray jet impact on soot emissions at the top of the pit of the piston has a significant effect on soot emissions. Analysis of the fuel and combustion visualization images in this study shows that this phenomenon is related to the distribution of fuel vapor in the squish zone and piston crown pockets in the combustion chamber.