Abstract Scope |
Oxidizer-rich and full-flow staged combustion rocket engines offer advantages in efficiency, thrust, and reusability over conventional gas generator engines. However, extreme combinations of O2 pressure and temperature in the ox-rich turbopump can limit engine life due to problems with metal ignition, burning, and oxidation-assisted fatigue. This talk will summarize initial insights from our investigation into the underlying mechanisms of frictional ignition, one of the ignition mechanisms of greatest concern and the root cause of several recent launch failures (Sea Launch’s NSS-8 and Orbital’s Orb-3). We test whether frictional ignition results from a breakdown of the oxide tribolayer that forms during a rubbing event using high-speed frictional ignition experiments, post-mortem characterization of recovered specimens, continuum mechanics models of sliding contacts, and thermochemical calculations of the structure and stability of oxide tribolayers. Our results suggest novel ignition-resistant superalloys for the next generation of reusable rocket engines. |