Preliminary experimental investigation of solid fuel scramjet combustor

A direct-connect static test-firing facility has been designed and built to carry out a preliminary experimental study on work process of solid fuel scramjet combustor. The stagnation pressure of 2.2 MPa and stagnation temperature of 1600K were provided at combustor inlet by a air heater. With this test facility, the self-ignition and sustained combustion were demonstrated under supersonic crossflow conditions in a scramjet configuration with no external aid. The results show that the regression rate increases first then decreases along the axial direction, and the maximum rate is located at the joint of cavity and cylindrical section, which is greater than 2 mm/s. As the combustion goes on, the fuel port diameter increases and static pressure drops fast in cavity and cylindrical section. Because the expansion ratio of diverging section decreases, the variation of static pressure in diverging section is smooth. Another combustor configuration with a sudden expansion step for flame-holding was investigated experimentally. The results show that the sudden expansion step is not suitable for flame-holding in solid fuel scramjet.