Vibro-acoustic analysis of variable thickness dual-functionally gradient CNT curved plates exposed to thermal environment

This study delves into the vibro-acoustic analysis of variable thickness dual-functionally gradient carbon nanotube (CNT) curved plates exposed to thermal environments, focusing on their vibration and sound transmission loss (STL) properties. The research introduces a novel curved sandwich structure with a dual-functionally gradient CNT core layer, which is composed of a functionally graded (FG) matrix reinforced with CNTs. The study considers both linear and nonlinear thickness variations, significantly reducing weight while maintaining load-bearing capacity. The dynamic equation and vibro-acoustic coupling model are established based on the first-order shear deformation theory (FSDT) and solved using Navier’s method combined with solid–fluid interface conditions. The analysis reveals that the frequency of the curved plate increases, and the sound insulation effect improves as the variable thickness parameter increases. The sound insulation effect of the DFG-CNT sandwich curved plate is better than that of the straight plate. However, curvature parameters of the curved plate greatly affect the structural vibration. Due to the softening effect, the frequency of the DFG-CNT sandwich curved plate decreases, and the sound insulation effect deteriorates as the temperature rises. The CNT distribution pattern has a relatively small impact on the free vibration. The study concludes that by establishing thickness gradients as a tunable design mechanism, precise weight-stiffness optimization for lightweight structures can be achieved. Future research can address nonuniform or gradient temperature changes and consider more complex external environments and boundary conditions, or intelligent materials with controlled vibro-acoustic response.