Stage separation is a critical event in multi-stage aerospace vehicles, demanding precise, reliable, and debris-free performance. Flexible linear shaped charges (FLSC) have emerged as an effective solution due to their high cutting efficiency, low weight, and ability to conform to structural interfaces. This study presents a comprehensive numerical and experimental investigation into an FLSC-based separation mechanism, with a focus on optimizing cut quality, minimizing debris, and validating simulation results through testing. Three distinct configurations were modeled using hydrocode software: a baseline flat plate setup (Case A) with an 8.4 g/m FLSC, a modified geometry with an R8 notch to guide fracture (Case B), and a reduced-charge configuration with 4.2 g/m FLSC for shock minimization and single plane cutting (Case C). The simulations employed coupled Eulerian–Lagrangian solvers, advanced material models, and embedded gauge points to capture detonation physics, jet formation, and structural response over microsecond timescales. Case B demonstrated significant improvement in debris reduction, while Case C achieved a clean single-plane cut with no debris. The final configuration was realized and tested experimentally using a flat plate test article. The results closely matched simulation predictions, showing precise separation, intact fasteners, and no flying fragments, thus confirming the effectiveness of the hydrocode-optimized design. This work highlights the potential of hydrocode simulations to guide cost-effective, time-efficient, and experimentally validated design of FLSC-based stage separation systems. The insights gained offer practical pathways for the development of next-generation separation mechanisms in space and missile applications, where precision and safety are paramount.
Kumar et al. (Wed,) studied this question.