非对称来流隔离段流动特性研究

1引言隔离段是超燃冲压发动机的一个重要气动部件,在进气道与燃烧室之间构建一气动热力缓冲区域,为进气道提供一个较宽的连续工作范围。通常超燃冲压发动机位于高超声速飞行器下表面的中后部,这样自由来流需要经过一段较长的前体后进入进气道,这就造成进气道进口靠近机体一侧存

Investigation of flow in isolators under asymmetric incoming airflow

In order to simulate the actual flowfield at the exit of supersonlc/hypersonic inlet, the flow in scramjet isolator is investigated under asymmetric incoming flow. A wind tunnel is designed under asymmetric incoming flow and the compression fields in the isolator have been investigated by wall static and pitot pressure measurements and by schlieren photography. Three incoming Mach numbers are considered, Mach 1.5, Mach 1.8 and Mach 2 respectively. The results indicate that the increase of the asymmetry of the flow at isolator entrance will lead to the increase of the shock train length in isolator for a given pressure ratio. Based on an analysis of flow asymmetry effect at isolator entrance on shock train length, a modified correlation is proposed to calculate the length of shock train. The predicted results of the proposed correlation show good agreement with experimental results.