Abstract: In order to maintain a satisfactory performance of hypersonic vehicle on the off-design points, many studies have been conducted with the variable geometry, including the Single Expansion Ramp Nozzle (SERN). A SERN model was studied by FSI (Fluid-Structure Interaction) numerical simulation method. In order to analyze the key effects of the dynamic force of the FSI, the minor effects of the other uncertainty and difficulties are avoided.The heat transfer and the gravity are not considered in this study. Then, the cases of adjustable SERN with the cowl on the different position were studied.The results show that the supersonic vibration appeares with the SERN cowl on the different position. Based on the analysis of the results, the following conclusions could be obtained. Firstly, the vibration characteristics are mainly dominated by the material parameters and the structure. Secondly, the vibration frequency is about the first order of the natural frequency and the oscillation of the lift is more severe than the thrust with different cowl position. Thirdly, as the cowl angle increases, the amplitude of the vibration increases. 

Key words: Scramjet;Single expension ramp nozzle; Fluid-structure interaction;Load;Vibration

摘要： 为了获得高超声速飞行器非设计点上较好的性能,包括单边膨胀喷管(SERN)在内的几何可调方案成为了目前研究的热点, 针对单边膨胀喷管开展了流固耦合的研究,重点分析流固耦合中的动态载荷问题,不考虑结构传热及重力的影响,对不同几何调节位置上的SERN开展了计算分析。结果表明在不同位置上,SERN唇口板均出现了超声速颤振。通过进一步分析,获得结论如下:(1)唇口板振动特点主要由材料属性和结构决定；(2)唇口板在不同调节位置上,振动频率大致均为结构的一阶振动频率, 喷管升力的振荡范围较喷管推力的振荡范围大；(3)随着唇口板角度的增加,唇口板振幅增大。 

关键词: 超燃冲压发动机;单边膨胀喷管;流固耦合;载荷;振动 