双层交错布置多孔喷嘴设计与仿真研究

针对高喷射压力下传统喷油嘴喷雾的碰壁比较严重以及传统多孔喷嘴喷雾之间易相互干扰等问题，设计了一种具有上下2层交错布置的多孔喷油嘴，阐明了双层交错布置多孔喷嘴的结构和理论依据，建立了喷雾及燃烧排放模型，研究了双层交错布置多孔喷嘴的喷雾特性及其结构参数对共轨柴油机燃烧与排放性能的影响.喷雾特性仿真表明，与传统喷油器相比，双层交错布置喷油嘴具有较短的喷雾贯穿距和更好的燃油空间分布特性.双层交错布置喷嘴的结构参数对高压共轨柴油机的燃烧过程和排放性能的影响研究表明，上层喷孔的喷射夹角采用大喷射夹角或下层喷孔采用小孔径，都可以使柴油机的燃烧及排放性能得到进一步改善.

Design and Simulation Research on Double-Staggered Arranged Porous Nozzle

For the serious phenomenon of the traditional nozzle spray run into a wall and the spray interference of general porous nozzle under high injection pressure, this paper designed a staggered arranged porous nozzle with upper and lower layers, clarified the structure and theoretical basis of the double staggered arranged porous nozzle, established the spray and combustion models to study the spray characteristics of the double staggered arranged porous nozzle and the influence of its structural parameters on combustion and emissions performance of the common rail diesel engine. The spray simulation shows that the double staggered arranged porous nozzle has a shorter injection distance and better spatial distribution of fuel properties compared with conventional nozzle. The influence of structural parameters of double staggered arranged porous nozzle on common rail diesel engine combustion and emission performance shows that the upper nozzle spray angle using a large one or under nozzle using a small diameter, can make the diesel combustion and emissions performance further improved.