Research on Acoustic Black Hole-Type Baffles for Suspended Water Tanks of High‑Speed Trains: Considering Vibration and Wave Suppression Characteristics

To mitigate structural vibrations caused by liquid sloshing inside the suspended water tank of high-speed trains and to prevent issues such as baffle fatigue failure and water leakage from tank cracking, this study designed an acoustic black hole (ABH)-type baffle that comprehensively considers both vibration and wave suppression performance. Based on acoustic black hole (ABH) theory, numerical simulations were conducted using the CFD software Fluent to analyze the vibration and wave suppression characteristics of the ABH-type baffle under lateral and longitudinal impact conditions. The influence of the position and number of ABH structures on the baffle’s performance was systematically examined. Finally, the structural strength and the vibration/wave suppression capability of the baffle were validated.The results demonstrate that the structural strength of the ABH-type baffle meets the design requirements. Compared to a conventional baffle, the ABH-type baffle reduces the liquid sloshing force inside the tank, lowers the peak sloshing pressure under various operating conditions, and decreases the surface vibration velocity of the baffle within its dominant vibration frequency range of 0–100 Hz. The optimal positions for the ABHs are at the 80% and 20% water-level lines on the baffle, and the best suppression performance is achieved when the center of the ABH is aligned horizontally with the liquid surface. Furthermore, the vibration and wave suppression capability deteriorates when the number of ABHs is either greater or fewer than three.