PSI - Issue 52

Feifei Ren et al. / Procedia Structural Integrity 52 (2024) 730–739 Author name / Structural Integrity Procedia 00 (2023) 000–000

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Fig. 3. The sensitivity analysis results of the dispersion curve with temperature for, (a) phase velocity; (b) group velocity.

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Fig. 4. The goodness fit of the group velocity for, (a) A 0 mode; (b) S 0 mode.

The goodness fit of the group velocity and the fit index are shown in Figure 4. It is observed that for both A 0 and S 0 modes, there exists a specific range within which the linear fit accurately represents the relationship between the group velocity and temperature, with a goodness of fit greater than 0.996. The fit index of the linear fit is presented in Figure 5, which represents the relationship between the group velocity and the temperature increment. This fit index can further provide insights into the temperature compensation factor for guided wave signal phase changes. From the observations of the figures, it is evident that the fit index remains relatively stable within the range of f · d : [300 kHz · mm − 840 kHz · mm] for A 0 mode and [0 kHz · mm − 500 kHz · mm] for S 0 mode. The sensitivity results indicate that the temperature-induced change of group velocity within a frequency and thickness range may be consistent, enabling further exploration and analysis of the temperature compensation for group velocity across di ff erent panel thicknesses.