Optimization of Fuel Depletion Sequence for Trim Drag Minimization of a Commercial Hypersonic Aircraft Powered by Liquid Hydrogen

This publication presents selected results from an ongoing experimental investigation into combustion processes and environmental aspects of ramjet and scramjet propulsion systems at the German Aerospace Center (DLR). The presented work forms part of a follow-up campaign to the European MORE&LESS project. The paper summarizes and compares selected experimental data on the influence of different injector configurations, namely parallel and transverse fuel injection, using gaseous hydrogen and liquid n-heptane as fuels. Furthermore, a film-cooled injector design is compared with an uncooled reference configuration to assess the impact of film cooling on injector pressure and temperature characteristics. In addition to the experimental results, an outlook on ongoing investigations employing advanced diagnostic techniques and additional fuels is provided. Finally, remaining research needs and the resulting adaptations of the experimental setup are discussed.