喷油嘴内部空穴流动试验研究  

Experimental Study on Cavitation Flow inside Nozzle

作　　者：郭立新[1] 施东晓 李康宁[1] GUO Lixin;SHI Dongxiao;LI Kangning(Wuxi Fuel Injection Equipment Research Institute,Wuxi 214063,China)

机构地区：[1]中国一汽无锡油泵油嘴研究所,江苏无锡214063

出　　处：《车用发动机》2021年第5期15-21,共7页Vehicle Engine

摘　　要：在比例放大透明喷油嘴空穴流动可视化试验台上,基于流体力学相似原理,在喷射压力为0.15~1.70MPa,背压为0.1MPa,环境温度为20℃条件下,使用高速数码摄影,研究了空穴产生、发展过程及对喷雾的影响,并分析了喷射压力、针阀升程对空穴流动的影响.试验表明:在喷油嘴内空穴流动是不稳定的,且会有膜状空穴和线空穴发生.随着喷射压力和针阀升程增大,膜状空穴和线空穴强度范围会增加.膜状空穴和线空穴都会使喷雾锥角增加,线空穴下喷雾对称度要好于膜状空穴.An experimental system of flow visualization was setup based on a transparent scaled-up vertical injector nozzle tip.Based on the similarity principle of hydrodynamics,the generation and development of cavitation flow and its effect on spray were investigated and the influences of injection pressure and needle valve lift on cavitation flow were analyzed with a high resolution and speed CCD camera under the injection pressure of 0.15 MPa-1.70 MPa,the back pressure of 0.1 MPa and the ambient temperature of 20℃.The experimental results show that the cavitation flow in the nozzle is unstable with the film cavitation and string cavitation.The strength range of film cavitation and string cavitation will increase with the increase of injection pressure and needle valve lift.Both the film cavitation and the string cavitation will increase the spray cone angle.In addition,the symmetry of string cavitation spray is better than that of the film cavitation spray.

关 键 词：喷油嘴 可视化 空穴 燃油喷雾 

分 类 号：TK421.43[动力工程及工程热物理—动力机械及工程]