Hui Li

Title : Analytic modeling and analysis of impact characteristics of composite cylindrical shells with an auxetic honeycomb core subjected to high velocity internal projectile impact

Abstract:

An analytical model is developed to investigate the impact characteristics of composite cylindrical shells with two fiber reinforced polymer (FRP) skins and an auxetic honeycomb core (AHC) subjected to high-velocity internal projectile impact. A strain rate fitting function method is proposed to accurately simulate the dynamic behavior of materials under high-velocity impact loading by updating the elastic moduli. Reddy's higher-order shear deformation theory is utilized to define the structural displacement components, and an improved Gibson theory is applied to determine the equivalent elastic moduli and Poisson's ratios of AHC. The delamination and fracture energy absorption mechanisms of the FRP skins and the core are studied, and the dominant failure modes such as fiber tension, fiber compression, matrix tension, matrix compression, and compression-shear failure of AHC are identified using a 3D Hashin criterion for the skins and a compression-shear coupling failure criterion for the core. The model is roughly validated by comparing the predicted high-velocity impact parameters with literature and ABAQUS simulation results. Furthermore, a high-velocity impact experimental system for penetrating impact tests of such shell specimens is established to obtain the residual velocity, specific energy absorption, ballistic limit, and damage areas on the inner and outer skins of the specimens, with the measured data being employed to give a solid validation of the proposed model. A comprehensive error analysis is also discussed, highlighting the error sources and their impact on the accuracy of such an analytical model.

Audience Take Away Notes:

• A novel composite cylindrical shell with two FRP skins and an AHC is fabricated
• An analytical model of such a shell is established to predict the impact parameters subjected to the internal impact of a high-velocity projectile
• The proposed model is validated through the comparison of literature, ABAQUS simulation, and experimental results

Biography:

Hui Li is a professor at Northeastern University, China. He has published more than more than 70 research articles in SCI/ EI journals and 60 Chinese invention patents, including 45 top-level SCI papers in Compos Sci Technol, Compos. B. Eng, Mech Syst Signal Process, Nonlinear Dyn., etc. He once was a vibration engineer in Shenyang Machine Tool Co, Ltd, a postdoctoral fellow at Shenyang Engine Research Institute, and a visiting scholar at Liverpool University in the UK and Hanyang University in South Korea. His research interest includes nonlinear vibration, vibration and impact modeling, dynamic thermal evaluation of porous, hybrid and multifunctional composite materials and structures.