AE detection for pipeline valve leakage based on HHT

作者：Liu, Gui-Jie; Xu, Meng; Wang, Xin; Jiang, Rui-Lin

来源：Journal of Vibration and Shock, 2012, 31(23): 62-66.

• Acoustic emission signal
• EEMD
• Ensemble empirical mode decompositions (EEMD)
• Hilbert marginal spectrum
• Hilbert transformations
• Intrinsic Mode functions
• Time-frequency resolution
• Valve leakage

To analyze the non-stationary feature of acoustic emission(AE) signal from pipeline valve leakage, a HHT method combining ensemble empirical mode decomposition(EEMD) and Hilbert transformation method was presented here. Using EEMD method, the detected leakage signal was self-adaptively decomposed into a series of intrinsic mode functions(IMFs). Then, those IMFs were analyzed using Hilbert spectrum and HHT marginal spectrum, the key characteristics of AE signal in valve leakage were extracted. It was shown that the proposed method can overcome limitations of nonlinear signal in time-frequency analysis, and can avoid the mode mixing caused by EMD method;the Hilbert spectrum has higher time-frequency resolutions comparing to STFT spectrum;by analyzing the Hilbert marginal spectrum, the main frequency of the leakage signal was determined;this HHT method can be successfully applied in acoustic emission testing of valve leakage.

• 出版日期2012-12-15
• 单位中国海洋大学