Flame Characteristics and Combustion Stabilization in a 75° Swept Strut Supersonic Combustor

In this paper, the flame characteristics and combustion stabilization mechanism of a three-step 75° swept strut combustor were studied experimentally under the flight condition of Mach 6. The shape of the stable combustion flame and the flame propagation process were captured by a visualization window mounted on the combustor side wall, and the pressure along the combustor during the ignition process was collected based on pressure sensors. The results show that the global flame establishment of the combustor can be realized under the effect of the wall kerosene injection. The linear change of the strut/wall equivalence ratio will directly affect the thermal choke position of the combustor, which will affect the flame propagation characteristics of the combustor and result in varying degrees of flame blowing off, flame attachment, and flame backpropagation. In addition, the combustion stabilization of the combustor can be achieved under the combined action of the strut and the thermal choke. The oxygen injection of the strut plays a more important role in the combustion stabilization. However, if the oxygen is removed, the thermal choke will play a more important role than the strut.