Sudden Expansion Of The Supersonic Combustion Chamber Structure Design

The scramjet has some advantages of high flow velocity, high specific impulse and wide operating range which become a viewpoint in the research field of power of Aeronautics and Astronautics. In the recent ten years, scramjet design, computational and experimental studies has been developed rapidly in the world.The most difficult problem in the design of scramjet is that, how to design an optimization configuration of supersonic combustor. Researchers have done much research for different combustor configurations. The configuration with backwind step is widely adopted in the design of scramjet combustor.Some related research papers for typical supersonic combustor have been reviewed and analyzed. The flow field and performance for several scramjet combustor configurations has been simulated and compared. The effects on the supersonic combustor performance of some factors were studied, including expanding area, step, cavity, fuel injection and so on. All these works done were hoped to be available for the combustor configuration design. In this paper, in order to study the effect of expanding area and backwind step on two kinds of combustor configuration, the result of numerical simulation and some experiment data has been analyzed and compared. All the research results show that the numerical simulation method used in this article can well simulate the combustor flow field and combustor performance. As the total expanding angle is the same, two-sides expending combustor configuration has higher performance than one-side expending combustor configuration. Furthermore, as the total step height is the same, the combustor configuration with one backwind step has higher performance than the combustor configuration with two backwind step.