Impulsive Response Analysis Using Transient Energy Distribution Analysis

Statistical Energy Analysis (SEA) and Energy Distribution Analysis (EDA) are suitable for predicting responses to stationary vibrations. These methods consider a structure of interest as an assembly of subsystems and analyze energy flows between the subsystems. In particular, EDA can analyze vibrations over the whole frequency range, while SEA is basically used only for high frequencies. However, these methods do not consider transient dynamic characteristics, so they are not applicable to the analysis of unsteady vibrations such as impulsive vibrations. This paper proposes transient EDA (TEDA) as is extension of EDA to impulsive responses. The proposed method is expected to be a suitable tool for impulsive analysis of huge structures like ships. The feasibility of the proposed method is examined through an experiment with a test structure composed of three flat steel plates. Also, the proposed method is compared with TSEA. We find that TEDA can predict the vibration energy of each subsystem more accurately than TSEA. Measurements of the energy response of a structure composed of three flat steel plates, including a coupling at right angles, showed specific energy transfer characteristics: the maximum energy of the end plate that is far from the input plate was larger than that of the second plate that is between the input and the end plates; and energy peak rise time of the end plate was faster than that of the second plate.