PSI- Issue 9

I. Shardakov et al. / Procedia Structural Integrity 9 (2018) 199–206 Author name / Structural Integrity Procedia 00 (2018) 000–000

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5

b)

a)

Fig. 5. (a) Vibrogram of the filtered signal; (b) amplitude evolution and its linear approximation in the logarithmic scale

The results of the experiment, which was performed according to the second scheme of the excitation of flexural torsional vibration modes (Fig. 3b) were processed in a similar way. The experimental dependences and the results of processing are presented in Fig. 6-8. The results of processing yielded the following characteristics of vibrations: eigenfrequency for a flexural-torsional vibration mode, exp 5630 Hz rot f  and the corresponding logarithmic decrement, x 3 e p 39.25 10 rot     .

a)

b)

Fig. 6. (a) Flexural-torsional vibration: vibrogram; (b) corresponding Fourier-image

a)

b)

exp 5630 Hz

rot f 

Fig. 7. (a) Vibrogram of a signal filtered in the vicinity of the eigenfrequency

; (b) corresponding Fourier image

a)

b)

Fig.8. (a) Vibrogram of the filtered signal; (b) amplitude evolution and its linear approximation in the logarithmic scale