Based on vibration analysis by means of multi-scale method, the dynamic model of 2.5D braided resin-based composite plates was updated using the modal test data, to obtain a model accurately reflecting its dynamic characteristics. Firstly, sensitivity analysis method of the natural frequency with respect to the elastic parameters was developed to modify the composite multi-scale dynamic model. It aims to identify the principal factors affecting the natural vibration characteristics of composite plates. Secondly, a composite multi-scale dynamic model updating method in combination with sensitivity analysis was established. A model updating program based on MSC.NASTRAN was devised. Finally, an updated dynamic model of the composite plates was obtained by exploring the modal test data. After the key elastic parameters were updated, the maximum natural frequency error between simulated and experimental data under different boundary conditions and yarn alignment directions of composite plates decreased from 10.44% to 2.39%, indicating a remarkable improvement in correlation. In addition, the proposed dynamic model updating method combined with free modal testing provides a new technical approach for experimental identification of equivalent elastic parameters of composites. © 2022, Editorial Department of Journal of Propulsion Technology. All right reserved.
