Transverse jet mixing and combustion experiments in hypervelocity flows

Transverse jet mixing and combustion experiments at a freestream velocity of 5 km/s have been conducted in the T5 free-piston shock tunnel at GALCIT. The experiments were performed in a 50 by 25 mm combustor model using a flush-mounted, Mach 1.7 single injector introducing the fuel at an angle of 15 deg relative to the main flow. The test conditions cover a range of freestream pressures from low values chosen to match previous experiments with the same duct in the HYPULSE expansion tube facility at GASL, to high pressures corresponding to the conditions closer to those in a real scramjet combustor. Tests with cold and hot hydrogen fuel were performed, the latter to better reproduce the fuel conditions of a scramjet propulsion system where the hydrogen will have to be used first as a cooling fluid. A small combustion-driven shock tunnel was used simultaneously with T5 to supply the hot fuel.