摘要
针对航空发动机浮环密封运行时,声发射信号易受外界噪声干扰,且特征信号难以提取的问题,提出一种基于免疫算法(immune algorithm, IA)和变分模态分解(variational mode decomposition, VMD)的声发射信号处理方法。首先应用免疫算法对变分模态分解中的模态数K和惩罚因子α进行优化,采用样本熵为亲和度函数,得到VMD算法中的最佳参数组合。其次,对原始信号进行分解得到若干模态分量(intrinsic mode function, IMF)并计算出各个分量的相对熵,选取差异小的分量进行重构得到降噪信号。仿真信号分析表明,IA-VMD方法可以获得最佳参数,在抗噪声干扰方面具有明显优势。最后,对浮环密封声发射信号降噪并进行特征提取,结果表明,采用IA-VMD方法能够在降噪的同时最大限度保留有效信息,获得表征浮环密封主密封面碰摩状态的声发射信号,为今后浮环密封故障诊断奠定基础。
To address the problem that the acoustic emission signal iseasily disturbed by external noise and the characteristic signal was difficult to be extracted during the operation of the aero-engine floating ring seal,an acoustic emission signal processing method based on the immune algorithm(IA)and the Variational mode decomposition(VMD)was proposed.Primarily the immune algorithm was applied to optimize the number of modes and penalty factors in the variational mode decomposition,and the sample entropy was used as the fitness function to obtain the best combination of parameters in the VMD algorithm.Moreover,the original signal was decomposed to obtain several modal components(Intrinsic mode function(IMF))and the relative entropy of each component was calculated,and the components with small differences were selected for reconstruction to obtain the noise reduction signal.The simulation signal analysis shows that the IA-VMD method could obtain the best parameters and has obvious advantages in the anti-noise interference.Eventually,noise reduction and characterization of the acoustic emission signal of the floating ring seal show that the IA-VMD method canretain the maximum effective information while noise reduction,and obtain the acoustic emission signal characterizing the friction state of the main seal surface of the floating ring seal,laying the foundation for future fault diagnosis of the floating ring seal.
作者
张帅
丁俊华
丁雪兴
力宁
ZHANG Shuai;DING Junhua;DING Xuexing;LI Ning(School of petroleum and chemical engineering,Lanzhou University of technology,Lanzhou 730050,China;AECC Human Aviation powerplant Research Institute,Zhuzhou 412002,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2024年第4期222-229,共8页
Journal of Vibration and Shock
基金
国家重点研发计划(2020YFB2010001)
国家自然科学基金项目(51565029)。
关键词
浮环密封
免疫算法(IA)
变分模态分解(VMD)
声发射
特征提取
floating ring seal
immune algorithm(IA)
variational mode decomposition(VMD)
acoustic emission
feature extraction
