Cavity flame-holder experiments in a model scramjet engine

Abstract

Supersonic combustion experiments are carried out using the T3 free-piston shock tunnel. Different shock tube fill pressures have various inflow conditions. Hydrogen fuel injection is located with a 15° slope before the cavity. Oblique shock is generated at the trailing edge of the cavity and reflects off the top and bottom wall. For non-reacting flow, floor static pressures for low equivalence ratio are similar to those for no fuel injection. As equivalence ratio is increased, static pressures are increased in the duct. For similar equivalence ratio, static pressures increase when total enthalpy is decreased. For reacting flow, the flame occurs near the cavity and the cavity acts as a flame-holder. The combustion is weak locally in the middle of the duct. The up-and-down pressure distribution in the duct means that the supersonic combustion is generated.