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Y. Liu et al.
waves in the stiffened panels with different number of stiffeners all have high energy
passing rate in the 100–200 kHz band.
14.5 Conclusion
In this paper, the propagation law of Lamb wave in stiffened panels with high stiffeners is studied based on finite element simulation. The influence of the number of
stiffeners on the Lamb wave signal is analyzed from the perspective of time domain
and frequency domain. The results show that:
1. The time domain characteristics of the signal indicate that the Lamb waves arrive
almost simultaneously in the models with different numbers of stiffeners, and the
number of stiffeners has no effect on the wave velocity of the Lamb wave. The first
wave trough of the Lamb wave will decay when passing through the stiffeners,
and the more the number of stiffeners, the more obvious the attenuation. The
same conclusion applies to the first crest.
2. The frequency domain characteristics of the signal indicate that the energy ratio
curve fluctuates with increasing frequency, and the effect of the stiffeners on the
Lamb wave is equivalent to a comb filter. Comparing the 6 models with different
numbers of stiffeners, the energy ratio curve is more moderate in the 200–500 kHz
band. In the 0–200 kHz band, the energy ratio curve changes drastically with an
obvious pass band. At the same time, the Lamb wave energy passing rate in the
100–200 kHz band is high and stable.
According to the above conclusions, Lamb waves of appropriate frequency band
can be selected to improve the signal to noise ratio and reduce the difficulty of
analysis in structural health state detection and non-destructive testing of stiffened
panel structures.
References
1. L. Zhang, D. Ozevin, D. He, W. Hardman, A. Timmons, A method to decompose the streamed
acoustic emission signals for detecting embedded fatigue crack signals. Appl. Sci. 8(1), (2018)
2. M.F. Haider, M.Y. Bhuiyan, B. Poddar, B. Lin, V. Giurgiutiu, Analytical and experimental
investigation of the interaction of Lamb waves in a stiffened aluminum plate with a horizontal
crack at the root of the stiffener. Sci. J. Sound Vib. 431, 212–225 (2018)
3. X. Bian, Y. Zhang, Y.B. Li, X.Y. Gong, S.J. Jin, A new method of using sensor arrays for
gas leakage location based on correlation of the time-space domain of continuous ultrasound.
Sensors 15(4), 8266–8283 (2015)
4. K. Grabowski, M. Gawronski, I. Baran et al., Time-distance domain transformation for Acoustic
Emission source localization in thin metallic plates. Ultrasonics 68, 142–149 (2016)
5. V. Meruane, P. Veliz, E.I. Droguett, A. Ortiz-Bernardin, Impact location and quantification on
an aluminum sandwich panel using principal component analysis and linear approximation
with maximum entropy. Entropy 19(4), (2017)
Y. Liu et al.
waves in the stiffened panels with different number of stiffeners all have high energy
passing rate in the 100–200 kHz band.
14.5 Conclusion
In this paper, the propagation law of Lamb wave in stiffened panels with high stiffeners is studied based on finite element simulation. The influence of the number of
stiffeners on the Lamb wave signal is analyzed from the perspective of time domain
and frequency domain. The results show that:
1. The time domain characteristics of the signal indicate that the Lamb waves arrive
almost simultaneously in the models with different numbers of stiffeners, and the
number of stiffeners has no effect on the wave velocity of the Lamb wave. The first
wave trough of the Lamb wave will decay when passing through the stiffeners,
and the more the number of stiffeners, the more obvious the attenuation. The
same conclusion applies to the first crest.
2. The frequency domain characteristics of the signal indicate that the energy ratio
curve fluctuates with increasing frequency, and the effect of the stiffeners on the
Lamb wave is equivalent to a comb filter. Comparing the 6 models with different
numbers of stiffeners, the energy ratio curve is more moderate in the 200–500 kHz
band. In the 0–200 kHz band, the energy ratio curve changes drastically with an
obvious pass band. At the same time, the Lamb wave energy passing rate in the
100–200 kHz band is high and stable.
According to the above conclusions, Lamb waves of appropriate frequency band
can be selected to improve the signal to noise ratio and reduce the difficulty of
analysis in structural health state detection and non-destructive testing of stiffened
panel structures.
References
1. L. Zhang, D. Ozevin, D. He, W. Hardman, A. Timmons, A method to decompose the streamed
acoustic emission signals for detecting embedded fatigue crack signals. Appl. Sci. 8(1), (2018)
2. M.F. Haider, M.Y. Bhuiyan, B. Poddar, B. Lin, V. Giurgiutiu, Analytical and experimental
investigation of the interaction of Lamb waves in a stiffened aluminum plate with a horizontal
crack at the root of the stiffener. Sci. J. Sound Vib. 431, 212–225 (2018)
3. X. Bian, Y. Zhang, Y.B. Li, X.Y. Gong, S.J. Jin, A new method of using sensor arrays for
gas leakage location based on correlation of the time-space domain of continuous ultrasound.
Sensors 15(4), 8266–8283 (2015)
4. K. Grabowski, M. Gawronski, I. Baran et al., Time-distance domain transformation for Acoustic
Emission source localization in thin metallic plates. Ultrasonics 68, 142–149 (2016)
5. V. Meruane, P. Veliz, E.I. Droguett, A. Ortiz-Bernardin, Impact location and quantification on
an aluminum sandwich panel using principal component analysis and linear approximation
with maximum entropy. Entropy 19(4), (2017)