RAMBURNER FUEL INJECTOR FOR ENDOTHERMIC FUELS

For sustained high speed flight (Mach 3-6), recent studies have shown that endothermic fuels are required to cool aircraft systems. Such a cooling system would deliver fuel to the ramburner in varying amounts of liquid and gaseous phases. This project proposes to experimentally investigate and develop an innovative dual-phase fuel injector prototype suitable for crossflow injection in ramburners. The fuel injector will be selected based on the following criteria: 1. Liquid spray atomization; 2. fuel penetration/distribution for liquid, gaseous, and combined liquid/gaseous fuel injection; 3. susceptibility to plugging/clogging; 4. design complexity. In Phase I, design concepts will be screened at ambient conditions using isothermal bench-scale tests. The liquid-phase fuel will be simulated using water and the gas-phase fuel will be simulated using CO2. The best designs will be isothermally tested in an existing Integral Fuel Injector/Flameholder (IFF) to show their overall feasibility. In Phase II, the best designs from Phase I will be tested in a combustion rig, under ramburner conditions, using endothermic fuels. The Phase II tests will document the performance of the new injectors under realistic conditions. If successfully demonstrated, the prototype will be tested and evaluated in a turboramjet engine demonstrator in Phase III.