Transient Vibroacoustic Control of a Shock-Loaded Inter-Connected Cylindrical Double Shell

Abstract

Double-wall cylindrical shells are widely used in applications where resistance to acoustic shock loading is critical. While the transient vibroacoustic behavior of single-walled shells has been extensively investigated, extending these analyses to double-wall cylindrical configurations introduces increased complexity due to multiple inter-shell acoustic reflections and strong coupling between acoustic fields and structural vibrations. These structures often feature mechanical interconnections between the shells to ensure structural integrity, load sharing, alignment, and enhanced resilience against static and dynamic loads. These links introduce additional pathways for vibration transmission and significantly influence the overall behavior of the system, thus making the analytical description of the coupled vibroacoustic response even more challenging. This study investigates the transient vibroacoustics of an inter-connected double-wall cylindrical shell subjected to an acoustic shock, considering fully coupled fluid-structure interactions. A comprehensive two-dimensional acoustoelastic model is developed in polar coordinates, incorporating the surrounding medium, the fluid occupying the inter-shell gap, and the fluid inside the inner shell. A semi-analytical solution method is employed to capture the time-domain evolution of acoustic fields and shell vibrations. The model's accuracy is verified by benchmarking against available data reported in the literature. Leveraging the passive dynamics of the system, we present a hybrid mechanism that integrates optimized nonlinear vibration absorbers with piezoelectric actuators to control the vibroacoustic behavior. The results demonstrate the effectiveness of the proposed hybrid mechanism in mitigating shock-induced acoustic pressure waves and enhancing the structural resilience of the double-wall cylindrical shell.