This paper studies the diffuser ' s influence on the fadw ' s running properties experimentally including the inner wall and outer wall of diffuser and the backpressure of the diffuser . to prevent the gas of fadw from leaking into the laser cavity because of the effect of layer and turbulence the leak - proof flakes are designed . first the method of the leak - proof flake design is studied and then its influence on the properties of fadw is studied experimentally 实验研究了扩压器对fadw工作性能的影响,提出了扩压器结构和超音速喷管相对布局参考数据;研究了气动窗口侧壁防漏片的结构对气动窗口性能的影响,并给出其工程设计方法;同时还研究了扩压器不同的背压对整个fadw作性能的影响,据此提出了扩压器与引射器结合的设计方案,从而为大压比、高性能的fadw的设计提供了进一步设计参考方法。