直喷汽油机喷油器积碳的特征  

Deposits Characteristics of Fuel Injector in GDI Engines

作　　者：周建伟[1] 裴毅强[1] 张延峰[1] 王莉 刘昌文[1] 韩欣[1] 

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]天津农学院工程技术学院,天津300384

出　　处：《内燃机学报》2015年第6期516-521,共6页Transactions of Csice

基　　金：国家自然科学基金资助项目(51306132)

摘　　要：采用电子显微镜、能谱分析仪研究了积碳分布区域、形貌特征和组成元素的基本特征;使用高速相机获得了喷孔出口区域燃油流动特性的图像,对影响积碳形成的湿壁现象和雾化特性进行了定性分析.结果表明:积碳在喷油器上可划分为7个分布区域,喷油器外表面的积碳程度较内表面严重,各喷孔堵塞不均匀;积碳有干燥粗糙、湿润光滑两种形貌特征;积碳固体颗粒中共检出5种非金属元素和9种金属元素,底座平面积碳的化学成分较丰富;喷油器壁面油膜和底座周围的高浓度混合气是不同区域积碳形成的主要物质来源.Distribution area, morphology characteristics and composition of injector deposits were studied using electron microscope and energy spectrum analyzer. Near field spray images near the nozzle exit were obtained with highspeed camera, and wall wetting phenomenon and atomization characteristics that influence deposits formation were analysed qualitatively. Results show that the distribution areas of deposits in the injector tip can be divided into 7 regions. Most of deposits distribute on the outside surface of injector. The degree of fouling is uneven between nozzles. Dryness-roughness and wetness-smoothness are the primary morphology characteristics of deposits. 5 nonmetallic elements and 9 metallic elements are detected in the deposits, and abundant chemical components are identified on the injector seat surface. The fuel film on the injector surfaces and rich mixture around the injector seat are believed to be the main source of deposits in different regions. © 2015, Chinese Society for Internal Combustion Engines. All right reserved.

关 键 词：直喷汽油机 喷油器积碳 分布区域 组成元素 雾化特性 

分 类 号：TK413[动力工程及工程热物理—动力机械及工程]