摘要
运用平面波理论分析了燃油管道水击振动产生的机理,计算了3缸机和4缸机不同压力和温度下水击波频率、共轨管声腔模态频率;利用有限元方法计算了燃油管总成声腔模态频率和振型、管道结构模态频率和振型;利用格子波尔兹曼方法(lattice Boltzmann method,LBM)模拟分析了第1缸喷油器针阀关闭后共轨管内水击波压力分布规律和第1缸~第4缸喷油器针阀分别关闭引起的共轨管轴向力变化规律。结合测量数据分析了共轨管水击振动噪声随发动机运行工况、管道结构、流场结构、声腔模态变化的规律。分析结果表明:喷油器针阀关闭产生的水击波压力引起的轴向冲击力冲击共轨管端产生振动噪声。振动噪声主要发生在靠近共轨管端部(即3缸机第1缸、第3缸,4缸机第1缸、第4缸)的喷油器针阀关闭后,与燃油管道声腔模态声压分布有关。水击振动噪声频率与管道结构模态振型和频率有关,水击振动噪声随发动机工况变化而变化,在共轨管与喷油器针阀之间的流道上设计合适的阻尼孔能有效衰减水击波能量,降低或消除共轨管端水击振动及其引起的敲击声。
Based on the plane wave theory,the mechanism of water hammer vibration in a common rail fuel pipe was analyzed,and the water hammer wave frequency and acoustic cavity modal frequency of the common rail fuel pipe were calculated with different pressures and temperatures on a three-cylinder engine and a four-cylinder engine. The modal frequencies and vibration modes of the acoustic cavity of the fuel pipe assembly and the pipeline structure were calculated with finite element modality analysis method. The distribution law of water hammer wave pressure in the common rail fuel pipe on the 1st cylinder,and the variation law of axial force in the common rail fuel pipe caused by the close of the needle valve of the injectar on the 1st to the 4th cylinder were simulated and analyzed with lattice Boltzmann method. The variation law of vibration and noise caused by water hammer in the common rail fuel pipe with engine operating conditions,pipeline structures,flow field structures,and acoustic cavity modallities were analyzed. The analysis results show that the axial force caused by the water hammer produced by the close of the needle valve of the injector impacts the ends of the common rail fuel pipe and produces vibration and noise. The vibration and noise is produced mainly by the two cylinder injectors which are close to the ends of the common rail fuel pipe,that is,the first and third cylinders of three-cylinder engine and the first and fourth cylinders of four-cylinder engine.And the vibration and noise is related to the pressure distribution of the acoustic cavity of the fuel pipe. The frequency of vibration and noise caused by water hammer is related to the structure modality and frequency of the pipeline. The vibration and noise changes with the working conditions of engines. An orifice on the channel between the common rail fuel pipe and the injector needle valve can effectively attenuate the water hammer energy,and reduce or eliminate the vibration and the rattle caused by the water hammer.
作者
田绍军
黎谦
常光宝
倪小波
李海平
TIAN Shaojun;LI Qian;CHANG Guangbao;NI Xiaobo;LI Haiping(SAIC-GM-Wuling Automobile Co.,Ltd.,Liuzhou 545007,China)
出处
《内燃机工程》
CAS
CSCD
北大核心
2022年第2期100-108,共9页
Chinese Internal Combustion Engine Engineering
基金
广西创新驱动发展专项基金项目(AA18242034)
柳州市科技计划项目(2018AA10501)。
关键词
水击波
阻尼孔
声腔模态
液压冲击
燃油管道
共轨管
喷油器
压力脉动
water hammer
orifice
cavity modal
hydraulic impact
fuel pipeline
common rail
fuel injector
pressure pulsation
