Acquisition of dispersion features of circumferential guided wave in a circular composite material pipe based on the matrix pencil method

A method that can obtain the circular pipe multi-modal guided wave dispersion data from the circular receiver array data was proposed using the matrix pencil method. Firstly, based on the residue theorem, the multi-modal circumferential guided wave superposition formula of the guided wave response signal in the frequency domain is given, and the Hankel matrix of the array guided wave signal is constructed. Then, the dispersion data of the guided wave is obtained by solving the generalized eigenvalues of the Hankel matrix. The noise data in the dispersion data can be suppressed by using the average of the forward and backward receiver array processing results. Finally, the measurement experiment of the circumferential guided wave signal in a carbon fiber composite circular pipe is designed. The frequency dispersion data of the circular tube circumferential guide wave is obtained by the matrix pencil method and compared with the theoretical dispersion curve simulated by the semi-analytical finite element algorithm. The good agreement between the theoretical dispersion curve and the experimental data shows that the proposed method has strong robustness, and even if the air-coupled transducers are used as the transmit-receiver array, the frequency dispersion data of the guided wave can be effectively obtained.