Failure Propagation Controlling for Frangible Composite Canister Design

The complexity in predicting the damage initiation and failure propagation controlling in composite structures is challenging. The focus of this paper is to design a potential component for new ship gunnels to make the composite canister affordable in structural applications by using a damage tolerant design approach. The design of a new tailgate configuration was investigated, taking into account the correct fragmentation of the structure to ensure a clear ejection while reducing the weight of the panels by exploiting the properties of the composite material. The complex geometry of the tailgate, the high impulse load, the energy transferred to the tailgate during missile impact, and how to safely break large panel flaps are elements that characterize the sizing of the composite component to meet the stringent ejection requirements in the life cycle of a missile during takeoff. The numerical simulations were performed using the LS/Dyna code and its explicit formulation was contemplated to take into account the geometrical, contact, and material non linearities

Design of controlled rupture structure for safe vector ejection

The design of structures, which have a controlled rupture, is a topic of interest of both civil and military industry and the definition of design guidelines and criteria can be helpful for future configurations. Automotive, aerospace and defence study solutions can be useful to meet the high-performance requirements of lightness and safety, and more the latest studies concerning composite materials and the relative fracture micromechanics can help to achieve these targets. The research activity of this work is focused on the numerical analysis with the aim to design a possible part for new Maritime Firing Tubes. In particular the design of new tailgate configuration was studied considering the correct structure fragmentation to ensure a clear ejection, while reducing the weight of the panels by exploiting the characteristics of the composite material. The goal of this research is the development of a scientific and methodological approach to the study of controlled rupture structure for the design and optimization of launcher tailgate. An innovative concept of hatch composed by just one carbon resin composite laminate is studied and by varying the geometric configuration it is possible to optimize the breaking path and the contact force. The complex geometry of the hatch, the high impulsive load, the energy transferred during the impact between a sort of missile and hatch, and the ways of safely breaking large flaps of panels are elements that have characterized the dimensioning of the composite in order to satisfy the stringent requirements about the ejection event in a missile lifecycle during its own firing. The focus is the evaluation of the material fragmentation behavior and element deletion followed by excessive deformation in controlled fragments closely distributed around one or several specific sizes in presence of high-speed environment