TY - JOUR
T1 - The zero-frequency component of bulk waves in solids with randomly distributed micro-cracks
AU - Sun, Xiaoqiang
AU - Liu, Hongjun
AU - Zhao, Youxuan
AU - Qu, Jianmin
AU - Deng, Mingxi
AU - Hu, Ning
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/9
Y1 - 2020/9
N2 - When a longitudinal wave (bulk wave) propagates in elastic solids with randomly distributed micro-cracks, the acoustic nonlinear behavior including the zero-frequency component and higher harmonics can be generated due to the clapping and slipping behavior of micro-cracks. In this paper, the analytical solution based on the bi-linear stiffness model of micro-cracks and the numerical simulation with random micro-crack modeling are implemented to investigate the behavior of the zero-frequency component. The theoretical and numerical results both show that the zero-frequency component of bulk waves can be generated by the micro-cracks, which is more sensitive than the conventional second harmonics. Meanwhile, we find that the acoustic nonlinearity parameter based on the zero-frequency component increases linearly with the crack density, the length of the micro-crack region and the fundamental frequency in the low-frequency region. Moreover, the zero-frequency component of the reflected waves is also investigated, indicating it can be used to locate the micro-crack region.
AB - When a longitudinal wave (bulk wave) propagates in elastic solids with randomly distributed micro-cracks, the acoustic nonlinear behavior including the zero-frequency component and higher harmonics can be generated due to the clapping and slipping behavior of micro-cracks. In this paper, the analytical solution based on the bi-linear stiffness model of micro-cracks and the numerical simulation with random micro-crack modeling are implemented to investigate the behavior of the zero-frequency component. The theoretical and numerical results both show that the zero-frequency component of bulk waves can be generated by the micro-cracks, which is more sensitive than the conventional second harmonics. Meanwhile, we find that the acoustic nonlinearity parameter based on the zero-frequency component increases linearly with the crack density, the length of the micro-crack region and the fundamental frequency in the low-frequency region. Moreover, the zero-frequency component of the reflected waves is also investigated, indicating it can be used to locate the micro-crack region.
KW - Bulk waves
KW - Micro-cracks
KW - Ultrasonic nonlinearity
KW - Zero-frequency component
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U2 - 10.1016/j.ultras.2020.106172
DO - 10.1016/j.ultras.2020.106172
M3 - Article
C2 - 32450428
AN - SCOPUS:85084959207
SN - 0041-624X
VL - 107
JO - Ultrasonics
JF - Ultrasonics
M1 - 106172
ER -