单液滴附着光学窗口的光谱透射特性模拟分析OA

The adhesion of droplets to optical glass surfaces,such as aircraft windshields and infrared detection win-dows,markedly degrades the spectral transmittance.The composite structure formed by a single droplet adhering to an optical window is investigated.The droplet morphology is reconstructed using Surface Evolver,considering the effects of surface tension and gravity.Spectral radiative transfer model for the droplet-on-window system is developed based on the theory of radiative transfer in participating media.The spectral transmittance is simulated via the Monte Carlo ray tracing method.The computational deviations caused by the idealized spherical-cap assumption for the droplet shape are discussed,and the influences of droplet size,contact angle,direction of incidence,and wavelength are analyzed.The re-sults demonstrate that when the droplet morphology is approximated as a spherical cap,the deviation in spectral trans-mittance increases with the droplet's characteristic size,reaching a maximum of 43.93％.The spectral transmittance in-creases with larger contact angles,exhibiting a variation of up to 0.2 at a characteristic droplet size of 2.0 mm.Further-more,the spectral transmittance at wavelengths below 2.5 μm is generally higher when light is incident from the droplet side than that from the glass side.