1. Beijing Aeronautical Technology Research Center, Beijing 100076, China;
2.State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and astronautics,Nanjing 210016, China
Abstract:Wave reflection and transmission in composite beams containing a semi-infinite delamination are studied analytically based on Timoshenko beam theory. Two extreme cases of delaminated surface conditions: non-contact(open) and fully contact(closed) delaminations, are considered respectively for a unidirectional composite beam. The analytical solution of reflection and transmission matrices for a semi-infinite delamination is derived. Then the power reflection and transmission coefficients are obtained, which depend on both frequency and the position of the delamination. Numerical results show the conservation of power transport. The power distribution is also investigated in this paper to describe the mode conversion between two flexural modes and one extensional mode. A finite element method is used to verify the validity of the analytical results.
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