温度分层均质压燃发动机燃烧和排放数值模拟  

Simulation of Combustion and Emissions in HCCI Engine with Charge-temperature Stratification

作　　者：黄豪中[1,2] 陈晖[1] 裴毅强[2] 余红东[1] 陆志思[1] 赵瑞青[1] 

机构地区：[1]广西大学机械工程学院,南宁530004 [2]天津大学内燃机燃烧学国家重点实验室,天津300072

出　　处：《农业机械学报》2010年第4期20-25,46,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：广西自然科学基金资助项目(桂科青0991008);中国博士后科学基金资助项目(20080430723);广西大学科研基金资助项目(XBZ090152)

摘　　要：通过修改SENKIN程序,建立起一个有质量交换和缸壁传热的9区化学反应动力学模型。以SKLE正庚烷简化模型作为燃烧反应动力学机理,利用该模型计算了发动机的主要燃烧参数和排放物含量。结果表明,该多区模型能够准确地模拟温度分层均质压燃发动机的燃烧和排放特性。在温度分层均质压燃发动机中,外核心区、壁面边界层和缝隙是CO和HC的主要来源。其中,在外核心区产生CO和HC是由于壁面边界层和缝隙内的未燃混合气在膨胀过程中流入该区被部分氧化或没有被继续氧化。NO_x主要来源于高温的内核心区。要同时获得高效燃烧和超低排放,应适当提高壁面温度。A nine-zone model accounting for both mass exchange and heat loss was developed by modifying the SENKIN program.Combining with the SKLE simplified chemical kinetics model of n-heptane,the model was used to simulate the combustion and emissions of homogeneous charge compression ignition（HCCI） engine with charge-temperature stratification.The results showed that the simulation is able to reproduce the major combustion and emission characteristics of the experiments very well.In HCCI engine with charge-temperature stratification,the outer core zone,the boundary zone and the crevice zone are the source of CO and HC emissions.The CO and HC emissions in the outer core zone result from the partial-oxidation and unburned fuels which flow into the outer core zone from both the boundary zone and the crevice zone at the expand stroke.Most of NO_x emissions are produced in the inner core zones with higher temperature compared to the other zones.High efficiency combustion and extra low emissions are achieved simultaneously by increasing the wall temperature properly in HCCI engine with charge-temperature stratification.

关 键 词：内燃机 温度分层 均质压燃 数值模拟 多区模型 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]