Sensitivity Analysis of Injection Characteristic to Structural Parameters of GDI Injector Nozzle Hole  

汽油直喷喷油器喷油特性对喷孔关键结构敏感分析

作　　者：Li Xinhai Wang Lu Cheng Yong Shang Xianshang 李新海;王璐;程勇;商显上(山东建筑大学机电工程学院,山东济南250101;山东大学能源与动力工程学院,山东济南250061)

机构地区：[1]School of Mechanical and Electronic Engineering,Shandong Jianzhu University,Jinan 250101,China [2]School of Energy and Power Engineering,Shandong University,Jinan 250061,China

出　　处：《内燃机学报》2024年第6期541-548,共8页Transactions of CSICE

基　　金：山东省自然科学基金资助项目(ZR2021QE065).

摘　　要：The nozzle inner-flow characteristic of the“spray G”injector was studied by the computational fluid dynamics(CFD)simulation,and the sensitivity of cycle fuel mass to the conicity and entrance radius of the nozzle hole were analyzed.Results show that the inner conicity of nozzle hole inhibits the development of cavitation phenomena,and increases the injection rate.While the outer conicity of nozzle hole promotes the diffusion of cavita-tion,leading to reductions of the liquid volume fraction of the nozzle outlet and the local flow resistance of the nozzle hole.The sensitivity of cycle fuel mass to inner-cone nozzle hole is stronger than that of the outer-cone noz-zle,especially at the smaller hole conicity.The increase of injection pressure enhances the sensitivity of the injection characteristics to the nozzle hole structure,in which inner-cone nozzle has higher sensitivity coefficient than the outer-cone nozzle hole.However,the increase of injection pressure aggravates the offset of liquid jet to the nozzle axis of the outer-cone nozzle hole.With the increase of the inner conicity of nozzle,the sensitivity of the injection characteristics to the entrance radius of the hole decreases.With the increase of the outer conicity of nozzle hole,the sensitivity of the injection characteristics to the entrance radius of the hole increases.采用计算流体动力学(CFD)方法研究了“spray G”喷油器喷孔内流动特性以及循环喷油量对喷孔锥度及入口倒角的敏感性.结果表明:喷孔内锥度会抑制空化现象产生并提升喷油速率.外锥孔会增强空化现象,导致喷孔出口液相占比减小,喷孔局部阻力减小;循环喷油量对内锥孔的敏感性比对外锥孔的敏感性更强,尤其在较小喷孔锥度附近;提高喷油压力,增强了喷油特性对喷孔锥度的敏感度,并且其对内锥孔的影响程度大于外锥孔.提高喷油压力,使外锥孔射流偏离喷孔轴线程度加剧;增加喷孔内锥度,喷油特性对喷孔入口倒角的敏感性整体下降,增加喷孔外锥度,喷油特性对喷孔入口倒角敏感性整体增强.

关 键 词：gasoline direct injection injector nozzle hole conicity nozzle hole entrance radius CAVITATION 

分 类 号：TK401[动力工程及工程热物理—动力机械及工程]