Research on Dynamic Characteristics Estimation Method for Predicting Ship Structural Health

In this study, to manage the ship structure's life cycle, the dynamic characteristics were identified by analyzing the measurement data of the ship's hydroelastic response, which affects the ship's structural health.The hydroelastic response of a ship has a significant impact on fatigue damage, which is an indicator of hull structural integrity, and it is important to analyze the hydroelastic response according to the dynamic characteristics of the ship.Data were acquired during operation using sensors installed on the ship, and a response matrix was constructed.The mode shape and natural frequency of the ship were obtained by applying the proper orthogonal decomposition (POD) technique to the response matrix.Due to the conditions of the target ship, a limited number of sensors were used, which led to difficulties in generating the mode shape, but this was resolved through the signal processing process.Finally, the results of a modal analysis using a finite element model were compared with the natural frequencies of the vertical two-node bending mode obtained in this study to confirm the validity of the analysis.The dynamic characteristics of the ship will be used to estimate hull fatigue damage and to study condition-based proactive maintenance (CBM+) of the ship.