超声速燃烧室内部流场具有流速快、温度高、背景光辐射强等特点,其流场显示较为困难。为此设计了一套脉冲纹影系统,该系统通过缩短曝光时间来冻结流场；另一方面,利用脉冲火花光源在短曝光时间内脉冲放电能量远高于燃烧室背景辐射能量的特点,有效消除了燃烧室背景辐射的影响。利用该系统对马赫数3.0的超临界煤油燃烧流场结构进行研究,得到了超临界煤油燃烧过程的清晰流场结构图像及其演化过程。

The flow-field in the supersonic combustor has the characteristics of high speed, high temperature, high background radiation, and so on. Thus,the visualization of flow-field in a supersonic combustor is difficult. According to above characteristics, a pulsed schlieren system was developed, and a short exposure time was chosen to freeze the flow-field. On the other hand, compared to the electric flash energy, the background radiation could be ignorable during the exposure time. Thereby, the effect of background radiation is eliminated effectively. The pulsed schlieren system is used to study the flow-field structures during the combustion process of supercritical kerosene in a Mach number 3.0 supersonic flow. Schlieren images clearly show flow-field structures and their evolutionary process.

国家自然基金重大研究计划重点支持项目(91016005);国家自然基金创新群体项目(10621202)。