被动预燃室喷孔布置对射流与燃烧影响研究  

Study on the Effects of Nozzle Layouts of the Passive Pre-chamber on Jet and Combustion Characteristics

作　　者：黄林辉 唐青龙[1] 孙久岭 尧命发[1] HUANG Linhui;TANG Qinglong;SUN Jiuling;YAO Mingfa(State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学先进内燃动力全国重点试验室,天津300072

出　　处：《工程热物理学报》2024年第8期2531-2539,共9页Journal of Engineering Thermophysics

基　　金：国家自然科学基金青年基金项目(No.52206166);国家自然科学基金重点项目(No.52130605)。

摘　　要：预燃室可提高点燃式发动机效率并降低氮氧化物排放,但预燃室喷孔布置对于射流和燃烧的影响尚不明晰。本文基于Converge三维仿真软件建立并标定了数值模型以进行模拟研究。针对被动式窄喉道预燃室结构,探究了三种预燃室喷孔布置方案:双排孔PC-1、上排孔PC-2和下排孔PC-3不同的射流和燃烧特性。结果表明:单排孔结构在当量或稀燃下具有较高的预燃室压差及射流速度,且具有较高的燃烧放热率和更提前的燃烧相位,其中PC-2结构稍优。双排孔结构则仅过浓条件下有较高射流速度和最提前的燃烧相位。另外,PC-2自预燃室向外传热比例最低,说明耗散于预燃室内的热量最低,而PC-1结构的自预燃室向外传热比例最高。综上所述,单排孔预燃室尤其是PC-2在大部分应用场景下更宜被发动机采用。The pre-chamber combustion can improve the efficiency of spark-ignition engines and reduce NOx emissions,but the effects of pre-chamber nozzle layouts on jet and combustion are not yet fully unraveled.In this study,a numerical model was established and calibrated based on the Converge three-dimensional simulation software for numerical research.For the passive narrow-throat pre-chamber structure,three nozzle layouts were investigated to uncover their jet characteristics and combustion mechanisms:PC-1 structure with dual-row nozzles,PC-2 structure with only upper-row nozzles,and PC-3 structure with only lower-row nozzles.The research results show that the single-row nozzles structure has higher pre-chamber pressure difference and jet velocity under equivalence or lean conditions,and has higher combustion heat release rate and earlier combustion phase,with PC-2 structure slightly superior especially.The dual-row nozzles structure PC-1 only has higher jet velocity and the earliest combustion phase under ultra-rich conditions.Besides,PC-2 has the lowest heat transfer through the pre-chamber wall,indicating that the heat dissipated in the PC-2 pre-chamber is the lowest,while PC-1 has the highest one.In summary,the pre-chamber with single-row nozzles,especially PC-2,has better combustion characteristics under most practical conditions and is most suitable for engine adoption.

关 键 词：预燃室燃烧 喷孔布置 射流特性 燃烧速率 

分 类 号：TK432[动力工程及工程热物理—动力机械及工程]