基于敏感IMF的再制造发动机振动状态研究

Vibration State of Remanufactured Engine Based on Sensitive IMF

为了提高再制造发动机质量,将总体平均经验模态分解方法分解方法(ensemble empirical mode decomposition,简称EEMD)及敏感IMF选择算法引入再制造发动机性能研究中。在对再制造发动机非稳态振动信号进行EEMD分解的基础上,首先,将相关系数引入到IMF研究中,分析各IMF分量与原始信号的相关性,并计算原始信号各IMF分量的敏感因子;然后,利用敏感IMF进行Hilbert变换,并对再制造发动机的振动状态进行分析。研究结果表明,采用EEMD分解算法及敏感IMF的边际谱能反映再制造发动机不同部位的振动状态,缸壁、缸盖、曲轴三处对振动的敏感频率是存在差异的,通过对发动机各主要部位振动情况的研究,可以有针对性地采用再制造工艺,从而为提高发动机再制造水平提供技术支持。

In order to improve the quality of remanufactured engine, ensemble empirical mode decomposition(EEMD) decomposition and sensitive intrinsic mode function(IMF) selection algorithm is introduced in the study of remanufactured engine performance. Based on the EEMD decomposition, interrelated coefficient is drawn into the study of IMF, the interrelation between the IMF weight and original signal is analyzed, the original signal IMF weight's sensitive determination is computed, then the sensitive IMF Hilbert commutation is used, and the vibration condition is analyzed. The results show that, using the EEMD decomposition algorithm and sensitive IMF marginal spectrum can reflect the vibration state on different parts of remanufactured engine. Cylinder, cylinder head, crankshaft, the sensitive frequency region of these three parts is different. Through the study of vibration condition of main parts, using manufacture technology, thus providing technology to improve Remanufactured Engine level. © 2017, Editorial Department of JVMD. All right reserved.