Modal stimulation analysis for acoustic-structure coupling system of the aluminum alloy metro vehicle cavity

Analyzing mode of metro vehicle cavity acoustic system is important for avoiding acoustic resonance and reducing interior noise. Using Finite Element Method, the car-body structure model and the cavity model for the aluminum alloy metro vehicle were established by means of reasonable simplification of actual structure. Acoustic-structure coupling model that considers the interaction between structure and sound field was also built. Based on the structure modal, acoustic modal and acoustic-structure coupling modal theories, modal analysis was conducted for the three models. The modal frequency and distortion section of structure, the acoustic modal frequency and sound pressure distribution in vehicle cavity as well as the change of the modal frequency and for the structure and cavity in acoustic-structure coupling system were analyzed. The results show that the interaction between structure and sound field can change the original modal frequency and the vibration mode of the car-body structure and interior cavity.