A mesomechanical particle-element model of impact dynamics in neat and shear thickening fluid kevlar
MetadataShow full item record
Advanced impact protection systems can experience serious damage due to contact with projectiles such as fragments or entire fan blades. To prevent catastrophic damage of such systems will require sophisticated materials and complex designs. The development of advanced ballistic protection systems will place increased emphasis on the use of composite materials and on numerical simulations to assess these new systems due to the cost and limitations of testing facilities and the increased capability of computing power. Example applications include the design of body armor for the protection of personnel, the design of fragment containment systems for aircraft engines, and the design of orbital debris shielding for the protection of manned spacecraft. The current research has developed a new mesomechanical particle-element material model for woven material impact response, a velocity dependent friction model to simulate yarn interactions, and a strain rate dependent model for Kevlar. In recent research, a new class of shear-thickening fluid (STF) composites has been developed for use in impact protection systems. Advancements in the current work include a Bingham shear stress model for STF effects and a new mixture equation of state for the STF Kevlar that captures the thermodynamic properties of the constituents. The numerical methods and material model developed in this research have been validated through the simulation of three dimensional impact experiments on different Kevlar target geometries. This dissertation also provides new data for fragment simulating projectile impacts on Kevlar with different boundary conditions and new data for aluminum cylinder and steel disk projectile impacts on neat and STF Kevlar with different boundary conditions.