基于WPES与MEEMD的船用主机振动研究  

Research on marine main engine vibration based on WPES and MEEMD

作　　者：吴刚[1] 江国栋 闫国华 陈晓东 WU Gang;JIANG Guo-dong;YAN Guo-hua;CHEN Xiao-dong(Merchant Marine College,Shanghai Maritime University,Shanghai 201306,China;Polar Research Institute of China,Shanghai 201209,China)

机构地区：[1]上海海事大学商船学院,上海201306 [2]中国极地研究中心,上海201209

出　　处：《舰船科学技术》2024年第4期103-108,共6页Ship Science and Technology

基　　金：上海市科技创新计划资助项目(20DZ2252300)。

摘　　要：为揭示船用长冲程低速柴油机健康状态下的振动特征,采用小波包能量谱(Wavelet Packet Energy Spectrum, WPES)和改进的总体平均经验模态分解(Modified Ensemble Empirical Mode Decomposition, MEEMD)结合的特征提取方法,对典型推进工况下低速机的表面振动信号进行3层小波包分解和重构。通过对能量占比较大的节点采用MEEMD方法进行分解,获得IMF1分量频谱。研究结果表明,在40%以下的较低发动机负荷时,各单次燃烧循环的振动波动较小,振动幅值基本一致。提升至50%以上发动机负荷时,燃烧引起振动波动明显增强。50%工况下,中高频能量占总能量的41.51%,为主要振动源。To reveal the vibration characteristics of marine long-stroke low-speed diesel engines under healthy conditions,a combination of wavelet packet energy spectrum(WPES)and modified ensemble empirical mode decomposition(MEEMD)was used to extract features for the three-layer wavelet packet decomposition and reconstruction of the surface vibration signals of the low-speed engine under propulsion conditions.The IMF1 component spectrum was obtained by decomposing the nodes with larger energy dominance using MEEMD method.The results show that at lower engine loads below 40%,the vibration fluctuations of each single combustion cycle are small and the vibration amplitude is basically the same.When the engine load is raised to more than 50%,the vibration fluctuation caused by combustion is significantly enhanced.41.51%of the total energy is in the medium and high frequency at 50%working condition,which is the main vibration source.

关 键 词：船用低速柴油机 小波包能量谱 改进的总体平均经验模态分解 振动特性 状态评估 

分 类 号：U164.121.1[交通运输工程]