直排型DF/HF化学激光器气流通道模型实验研究

 为了探寻直排型连续波DF/HF化学激光器的起动特性，建立了一套化学激光器气流通道单喷管小型模型实验装置，通过选用不同的气体（冷气流）作为工作介质和不同的扩压器进行实验，分别研究了工作介质的气动参量对模型起动特性和扩压器喉道最小面积的影响，并与1维定常流理论的计算结果作了比较。最后分析了基区对模型起动特性的影响，比较了两种类型基区的差异。实验结果表明:对于直排型连续波DF/HF化学激光器，采用大比热容比、小相对分子质量的介质作为引射气流，喷管出口和基区之间带有一个向内的圆角，对提高DDCL整体性能是有利的。

Experimental investigation on small-scale model of gas channel in directly drained CW DF/HF chemical lasers

To study the starting characteristic of directly drained CW DF/HF chemical lasers(DDCL), a single-nozzle small-scale model of DDCL gas channel was set up, and a series of experiments were conducted with different working mediums and several diffusers. The effect of gas dynamic parameters of medium on the starting characteristic and minimum area of diffuser throat was also studied. The experimental results are compared with those caculated by one-dimension Steady State Theory. In addition, the effect of the base of the nozzle on the starting characteristic is discussed, and the comparison between two types of bases is made. The result indicates that the most effective means for improving the performance of DDCL is to operate with high specific heat ratio, low molecular weight primary gas an