柴油机喷嘴入口圆角对线空化影响的试验研究  

Experimental Research on the Influence of the Entrance Corner on String Cavitation in Diesel Engine Nozzle

作　　者：曹天义 何志霞 孙申鑫 陈舟 周晗 管伟 CAO Tian-Yi;HE Zhi-Xia;SUN Shen-Xin;CHEN Zhou;ZHOU Han;GUAN Wei(School of Energy and Power Engineering,Jiangsu University,Zhenjiang 212013,China;Institute for Energy Research,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学能源与动力工程学院,镇江212013 [2]江苏大学能源研究院,镇江212013

出　　处：《工程热物理学报》2020年第3期771-775,共5页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51776088);江苏省自然科学基金资助项目(No.BK20161349).

摘　　要：柴油机喷嘴内的线空化是一种呈现线状形态的特殊空化现象,具有高瞬态性。本文利用自搭建的稳态试验台,设计了双孔min-SAC比例放大喷嘴。并在稳定喷射压力和固定针阀升程条件下开展了试验研究。研究表明,随着喷射压差的升高,喷嘴内部线空化程度随之增加;喷孔入口圆角会影响喷嘴内部涡旋运动,进而影响线空化的分布特征;在高针阀升程下,几何诱导空化对线空化有促进作用;当喷孔入口存在倒圆角时,喷嘴内几何诱导空化被明显抑制,线空化分布特征明显不同。The string cavitation in the nozzle of the diesel engine is a special cavitation phenomenon with a linear morphology,which has high transient nature.In this paper,a two-hole min-SAC proportional-magnification nozzle is designed using a self-built steady-state test bench.And experimental studies were conducted under the conditions of stable injection pressure and fixed needle valve lift.The study shows that with the increase of injection pressure difference,the degree of cavitation inside the nozzle increases;the orifice-entrance corner radius affects the vortex flow inside the nozzle,and then affects the string cavitation distribution;The geometry induced cavitation promoted the cavitation in the high needle valve lift in the high needle valve lift.geometry induced cavitation is significantly suppressed by the bigger corner radius and string cavitation distribution shows different characteristics with different corner radius.

关 键 词：柴油机 线空化 入口圆角 涡旋运动 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]