To address the characteristic that dry gas seal acoustic emission signals are susceptible to background noise interference,a denoising method based on complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and adaptive collaborative wavelet threshold filtering is proposed.CEEMDAN decomposes the dry gas seal acoustic emission signal to obtain a series of intrinsic mode function (IMF) components.Based on the weak correlation of IMF components containing higher noise,an autocorrelation attenuation indicator is constructed to automatically screen noise‑contaminated IMF components.Wavelet threshold denoising processes the noisy components,which are then reconstructed with the remaining components to obtain the denoised signal.Validation using simulated signals and experimentally acquired real dry gas seal acoustic emission signals shows that,compared with conventional wavelet threshold denoising methods,the signal‑to‑noise ratio (RSN) increases by an average of 4.91 dB,and the root mean square error (ERMS) decreases by an average of 44%.Compared with methods without autocorrelation attenuation‑based IMF screening,RSN increases by an average of 0.45 dB,and ERMS decreases by an average of 4.8%.After denoising,the peak characteristic frequencies in the spectrum of real acoustic emission signals become clearer,with significant background noise removal.This study provides support for dry gas seal fault prediction and health management technologies.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |