高速飞行器在大气层中飞行,光学头罩与来流相互作用,其温度和应力应变在飞行过程中会动态变化,引起头罩材料折射率的改变,进而影响光线传输。文中在对飞行过程中球形头罩温度和应力应变动态模拟的基础上,计算随时间变化的折射率场,并利用光线追迹方法计算光线通过头罩出射面的光程差,通过光学评价方法以及图像退化仿真直观得出其对头罩光传输的影响。结果表明,头罩温度和应变变化对光传输的影响较大,并且随着飞行速度的提高变得更为严重。 High-speed aircraft flying in the atmosphere, the optical hood and the flow interaction, the temperature and stress-strain in the course of the flight will change dynamically, causing the hood material refractive index change, thereby affecting the light transmission. Based on the dynamic simulation of the temperature and stress-strain of the spherical hood during the flight, the refractive index field changing with time is calculated and the optical path difference of the light passing through the exit surface of the hood is calculated by optical tracing method. As well as the image degradation simulation intuitively derived its impact on the headlight optical transmission. The results show that the change of temperature and strain of headgear greatly affects the light transmission, and becomes more serious as the flying speed increases.