Parameters such as fuel injector orientation, fuel flow rate, and stagnation temperature affect scramjet engine operation. In this work, three fuel injection methods were used to supply the combustor of a generic cavity-based scramjet flowpath with gaseous ethylene: upstream normal (up1), upstream angled (up2), and downstream normal (down1). Various combinations of fuel flow rates and fuel injection methods were explored using two stagnation temperatures ( and ) and one stagnation pressure () for a Mach-1.8 facility nozzle. The pre-ignition local equivalence ratio () in the cavity was leaner and less sensitive to global with up1 fueling than up2 fueling. For reacting conditions, up1 fueling required a higher global than up2 fueling to obtain the same specific stream thrust metric, calculated from pressure measurements along the flowpath. Redistributing fuel from up2 to down1 resulted in a lower specific stream thrust metric, but redistribution from up1 to down1 produced a higher specific stream thrust metric. The range of attainable global shifted to richer values with a step increase in stagnation temperature due to the reduced ratio of heat release from a given quantity of fuel relative to the total flow enthalpy.
Effect of Fuel Injection Strategy on Generic Scramjet Combustor Operation
Journal of Propulsion and Power ; 41 , 2 ; 150-163
01.03.2025
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch