A guided missile is a weapon system used in the interception of a ballistic missile using kinetic energy of a kill vehicle. The DACS (Divert and Attitude Control System) is a quick reaction propulsion system and subsystem of a kill vehicle that provides control over positions of a kill vehicle. The DACS allows for the interception of its target with greater accuracy and reliability. A Kill vehicle needs to move at high speed in a bid to intercept a ballistic missile after detecting a target. Thus, the weight reduction design of DACs system is required. The DACS operates under high temperature and pressure environment. In this study, one-way FSI (Fluid and Structure Interaction) analysis were conducted for various types of weight reduction valve model to validate its robustness. Through this process, we suggest an optimized weight reduction valve model

Elastomeric O-ring seals are widely used in static and dynamic applications due to their excellent sealing capacity, and availability in various costs and sizes. One of the critical applications of O-ring seals is solid rocket motor joint seal. In this, the operating hot gas must be sealed during the combustion time. In this study, we analyzed the behavior of O-ring compressed and highly pressurized by using the finite element method. The numerical analysis technique was verified through the comparison of analytical model and FE results. By using the verified FE method, the contact stress profiles at the sealing surfaces were investigated. It was found out that the contact stress profiles and deformation behaviors of the Oring are affected by friction coefficient, extrusion gap and stress relaxation considerably.