Underwater Impact of Composite Structures

Abstract

Fiber reinforced polymer composite structures have very comparable mass densities to that of water. As a result, the effect of the Fluid-Structure-Interaction (FSI) is much greater for those composite structures than for conventional metallic structures. As a result, this study investigates the effects of FSI on composite structures. A series of underwater impact testing has been conducted to understand the dynamic responses of composite structures coupled with the FSI effects. Both air-backed and water-backed underwater impacts are considered and their behaviors are compared to the dry impact test results in order to determine the FSI effects. Furthermore, multiphysics-based computational analyses have been undertaken so as to better understand and interpret the experimental results. The results of this study will provide knowledge necessary to apply composite materials to underwater structural applications.

Measuring the Effect of Strain Rate on Deformation and Damage in Fibre-Reinforced Composites: A Review

“…Dropweight experiments where composite plates were loaded on the surface of [284] or immersed in [285] water have also proved insightful. Owens et al reflected on the importance of fluid-structure interaction (FSI) effects in relatively dense fluids such as water [285].…”

“…Dropweight experiments where composite plates were loaded on the surface of [284] or immersed in [285] water have also proved insightful. Owens et al reflected on the importance of fluid-structure interaction (FSI) effects in relatively dense fluids such as water [285]. 'Added Virtual Mass Incremental' factors, that is to say the ratio of kinetic energy in water to that in the plate, were on average eight times greater in the air backed case and nearly four times higher in the water-backed case.…”