Two-dimensional Chebyshev pseudo spectral modal curvature and its application in damage detection for composite plates

To overcome the unstable problem in the classical modal curvature method, the two-dimensional Fourier spectral modal curvature method has been proposed in the former work of authors. The existences of the wrap-around effect and the Gibbs phenomenon in the Fourier spectrum-based method, however, necessitate the use of periodic extensions, which affects the efficiency of the modal curvature algorithm. To address the above problems, the two-dimensional Chebyshev pseudo spectral modal curvature is proposed in this work. The presented method inherits the spatial filtering capability and the spectral accuracy of the Fourier spectral modal curvature, and features an efficient modal curvature algorithm in absence of the periodic extension. Numerical and experimental validations are performed on composite structures. Validations show that the proposed method is accurate and effective in the damage detection for the two-dimensional composite structures.