A power flow mode approach dedicated to structural interface dynamic characterization

This study is related to structural vibration transmission at low frequencies and aims to propose a new approach to dynamically characterize the interface between different substructures of a complex coupled structure. A power flow mode method based on the imaginary part of the dynamic flexibility matrix is presented, which allows determining eigenvalues and eigenvectors representing qualitative and quantitative information on the power flowing inside the structure, respectively. It is further applied to study the power transmitted at the interface, making it possible to identify the direction associated to the dominant power flow patterns and to quantify their contributions. Specific properties dealing with moment excitation and mid-frequency approximation are also detailed to provide complementary insights into their dynamic meaning and behavior.