Investigation of an intake injected hot-wall scramjet

Injecting fuel on the intake of a scramjet allows the fuel and air to mix before entering the combustion chamber. This allows for a reduction in combustion chamber length, a major contributor to scramjet drag. This investigation aims to check if any combustion is occurring on the intake when the intake wall is hot. Gaseous Hydrogen fuel was injected at an angle of 45 degrees to the freestream approximately halfway along the intake of a two-dimensional scramjet model. The T4 shock tunnel, an impulse testing facility, was used to produce a hypersonic flow with freestream enthalpy of 3.0MJ/kg and Mach number of 6.5. The model was modified such that the intake wall could be heated to temperatures experienced in continuous flight. A pressure rise on the intake or an increase in the initial shock angle after the fuel was injected would indicate the occurrence of intake combustion. Neither of these things was observed in current experiments consistent with no ignition on the intake. The experimental procedure and results are discussed in this paper and compared with theoretical results