李雁飞, 郭恒杰, 马骁, 王建昕, 袁亚飞, 居钰生.不同背压下GDI油束的喷雾过程研究[J].内燃机工程,2017,38(3):52-59.
不同背压下GDI油束的喷雾过程研究
Spray Characteristics of GDI Jet under Varied Back Pressure
DOI：
关键词:内燃机  汽油直喷  喷雾  破碎  相位多普勒粒子测试技术
Key Words:IC engine  gasoline direct injection(GDI)  spray  atomization  phase Doppler particle analyzer
基金项目:中国博士后科学基金项目（2013M540940）
作者单位
李雁飞, 郭恒杰, 马骁, 王建昕, 袁亚飞, 居钰生 1.清华大学 汽车安全与节能国家重点实验室, 北京 100084； 2.中国一汽无锡油泵油嘴研究所, 无锡 214063 
摘要点击次数: 4960
全文下载次数: 2984
摘要:在定容弹中, 利用高速摄影和相位多普勒粒子测试技术研究了背压对汽油直喷多孔喷油器一油束的喷雾过程的影响, 背压变化范围为绝对压力0.05 MPa~0.50 MPa。研究结果表明：在不同的背压下, 均发现了目标油束往喷油器轴线偏转的趋势, 这是由目标油束两侧压差而引起；油束的偏转同时导致了油滴直径分布的变化。在喷雾发展过程中, 在大气压力和负压下, 不同径向位置的油滴速度在一定时间内呈双峰分布状, 而在高背压下仅呈现单峰分布, 这是由高速射流带来喷雾内外侧压力不平衡和汽油的低饱和蒸汽压引起喷孔出口速度分布变化共同作用而导致。
Abstract:One of the five jets issued from a five-hole injector used for gasoline direct injection（GDI） engines was carefully studied with the phase Doppler particle analyzer（PDPA） and high-speed imaging techniques to investigate the effect of back pressure on a fuel jet development. The tests were carried out in a constant volume vessel with the absolute ambient pressure ranging from 0.05 to 0.50 MPa. The result shows that the trajectory deviation of the target jet is observed under different back pressures, which is due to the pressure difference between the inner and outer sides of the target jet. The trajectory deviation affects the droplet size distribution. In addition, the spray at the sub-atmospheric or atmospheric ambient pressures exhibits more complicated process than that at elevated ambient pressure. Under the sub-atmospheric and atmospheric conditions, the spray tip becomes obtuse and the droplet velocity at different radial positions shows a “double peak” distribution inside the spray within a certain time, rather than a “single peak” distribution at elevated ambient pressure. It is believed that the ambient pressure imbalance caused by high-speed jet and the nozzle exit velocity distribution resulting from lower vapor pressure of gasoline could account for the difference.
查看全文  HTML   查看/发表评论