汽车工程 ›› 2023, Vol. 45 ›› Issue (5): 836-844.doi: 10.19562/j.chinasae.qcgc.2023.05.013

所属专题: 发动机&排放专题2023年

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多次喷射下压力波动对喷嘴内流及近场喷雾影响试验研究

魏云鹏1,范立云1(),张瀚文1,礼博1,顾远琪1,冷先银2   

  1. 1.哈尔滨工程大学动力与能源工程学院,哈尔滨  150001
    2.江苏大学能源研究院,镇江  212013
  • 收稿日期:2022-11-10 修回日期:2022-12-11 出版日期:2023-05-25 发布日期:2023-05-26
  • 通讯作者: 范立云 E-mail:fanly_01@163.com
  • 基金资助:
    国家自然科学基金(51879059);中央高校基本科研业务费专项资金(3072022GIP0303)

Experimental Research on Influence of Pressure Fluctuation on Nozzle Flow and Near Field Spray Under Multiple Injections

Yunpeng Wei1,Liyun Fan1(),Hanwen Zhang1,Bo Li1,Yuanqi Gu1,Xianyin Leng2   

  1. 1.College of Power and Energy Engineering,Harbin Engineering University,Harbin 150001
    2.Energy Research Institute,Jiangsu University,Zhenjiang 212013
  • Received:2022-11-10 Revised:2022-12-11 Online:2023-05-25 Published:2023-05-26
  • Contact: Liyun Fan E-mail:fanly_01@163.com

摘要:

为研究多频压力波动与喷嘴内流的因果关系以及对近场喷雾的影响机理,采用高速显微成像技术,开展了不同共轨压力下多次喷射过程真实尺寸锥形孔喷嘴可视化试验研究。同时通过高压传感器测量,得到喷嘴入口压力波动数据。研究结果表明:主喷过程喷雾锥角呈靴型趋势,由发展期、转化期、稳定期和衰减期组成,其整体趋势受喷射压力的影响,过程中存在空化形式的转变。预喷和后喷等小油量喷射过程中,存在针阀升程波动导致的不一致性。喷嘴处压力降与循环喷油量水平呈正相关,空化形式的转变影响了压力波动频率和传播速度。其中几何诱导空化形成时,压力呈低频波动,而线空化形成时,产生高频压力波动趋势。

关键词: 真实尺寸锥形孔喷嘴, 近场喷雾, 压力波动, 多次喷射, 流动空化特性

Abstract:

To study the causal relationship between the multi-frequency pressure fluctuations and the characteristics of the internal flow of nozzle, as well as the influence mechanism on the near-field spray, the high-speed microscopic imaging technology is used to carry out visualization experimental study on the real-size tapered hole nozzles during the multiple injection process under different common rail pressures. At the same time, the high-pressure sensor is used to measure the pressure fluctuation data of the nozzle inlet. The research results show that the spray cone angle shows a boot-shaped trend in the main injection process, which consists of the development period, the transformation period, the stable period and the decay period. The overall trend is affected by the injection pressure, and there is a change of cavitation form in the process. In the process of small fuel injection such as pre-injection and post-injection, there are obvious inconsistencies caused by the fluctuation of the needle valve lift. The pressure drop at the nozzle is positively correlated with the level of cycle fuel injection quantity, and the cavitation characteristics affect the frequency characteristics and propagation speed of the pressure fluctuation. When the geometrically induced cavitation forms, the pressure fluctuates at a low frequency.Whenline cavitation forms, a high frequency pressure fluctuation trend occurs.

Key words: real-size tapered hole nozzle, near-field spray dynamics, pressure fluctuations, multiple injections, flow cavitation characteristics