柴油机喷嘴喷孔非对称结构对近场喷雾特性的影响  

The Effect of Asymmetric Nozzle Hole Geometry of a Diesel Nozzle on the Near-Field Spray Characteristics

作　　者：吴玉强[1] 王谦[1] 高志胜[1] 何志霞[1] 孙伟[1] 郦赟 

机构地区：[1]江苏大学能源与动力工程学院,镇江212013

出　　处：《内燃机工程》2016年第6期170-175,共6页Chinese Internal Combustion Engine Engineering

基　　金：国家自然科学基金重点项目(51276084;51176066);江苏省高校优势学科建设工程资助项目(2010);江苏省工业支撑计划项目(BE2010198)

摘　　要：以某型国产单孔柴油喷油器为研究对象,采用X射线CT成像技术获取了喷嘴精确几何结构,发现了喷孔入口圆角的不对称性;同时采用长工作距离显微镜头结合高速可控闪光显微摄影技术,获得了喷油器喷孔下方3mm内近场喷雾图像,发现了喷雾的非对称现象,研究了喷孔非对称结构对柴油喷雾近场特性的影响。研究结果表明:喷孔入口为棱角时能够促进近场喷雾破碎;启喷阶段,喷雾轮锥角θ1和锥角θ2出现分离点,分离点之后θ1小于θ2;喷雾稳定阶段,喷孔非对称结构对近场喷雾特性的影响最为显著,圆角侧喷雾初次破碎很差,尖棱侧喷雾初次破碎很细,有大量液丝产生。针阀落座阶段,近场喷雾锥角出现结合点,结合点出现之前喷孔非对称结构的影响依然存在,结合点出现时,尖棱侧近场喷雾轮锥角骤减为零。By taking a domestic single-hole sac-type diesel injector as the research object, the precise nozzle geometry of the injector was measured based on the x-ray CT scan technology, and the asymmetry nozzle inlet fillet was observed. Moreover, the effects of the asymmetric nozzle hole geometry on the near- field diesel spray characteristics within 3 mm below its nozzle hole exit were investigated by means of a long- distance microscope combined with high speed controlled flash moro photography techniques. The results show that the sharp edge of nozzle inlet can promote the near-field spray broken. In the beginning the spray cone angles θ1 and θ2 appear separation point, after which the spray cone angle θ1 is less than θ2. In the stable period of injection, the asymmetric nozzle hole geometry has significant influence on the near-field spray

关 键 词：内燃机 喷油器 喷孔结构 近场喷雾 轮廓角 

分 类 号：TK421.43[动力工程及工程热物理—动力机械及工程]