文华,李玉杰,姜光军,梁帅帅.针阀运动对断油阶段空化和倒吸的影响[J].内燃机工程,2019,40(4):26-32.
Influence of Needle Valve Movement on Cavitation and Ingestion in Nozzle at the End of Injection
DOI:10.13949/j.cnki.nrjgc.2019.04.005
Key Words:injector nozzle  end of injection  valve movement  ingestion  cavitation
Author NameAffiliation
WEN Hua, LI Yujie, JIANG Guangjun, LIANG Shuaishuai College of Mechanical and Electrical Engineering, Nanchang University, Nanchang 330031, China 
摘要点击次数: 3513
全文下载次数: 1877
Abstract:Based on the volume of fluid method and overlapped grid technology, the fuel flow characteristics in a diesel engine injector nozzle during the ending of injection were studied through the three-dimensional simulation. The cavitation and ingestion in a transparent nozzle before and after the end of injection were investigated by visual experiment, and the effect of needle valve movement on the cavitation and ingestion was analyzed. The experimental results were consistent with those of the simulation. The results showed that during the seating process of the needle valve, the cavitation at the orifice was earlier than that at the pressure chamber, but the maximum cavitation at the pressure chamber was larger than that at the orifice. A quantitative analysis of the cavitation and ingestion indicated that the collapse of the cavitation was the direct cause of the ingestion. At the same time, the cavitation and ingestion in three nozzles of different needle valve seating speeds were also simulated. The results show that the cavitation at the pressure chambers of the three nozzles is different, showing that the cavitation increases with the increase of the needle valve moving speed; and the cavitation at the orifices of the three nozzles is basically equal. Finally, a new value reflecting the cavitation in a nozzle during the ending of injection was derived by a theoretical derivation, which can be used to explain the mechanism of cavitation generation in a nozzle and the influence of the needle valve movement on the cavitation and ingestion in a nozzle.
查看全文  查看/发表评论  下载PDF阅读器