Multi-band camouflage design with thermal management

Abstract

Abstract Space vehicles need to be able to hide themselves effectively in some specific scenarios; however, existing camouflage designs do not fully realize the "stealth" of a variety of existing detectors, and a large distance is required to meet the needs of all-round applications. We propose a \(\text{G}\text{e}/\text{Y}\text{b}{\text{F}}_{3}\) multilayer wavelength-selective emitter that covers more wavelengths with better camouflage effect and radiation cooling than previous developments. In addition, our emitter substantially reduces the implementation difficulty and cost of detection instruments while greatly improving the stealth effect and survivability of space vehicles in different environments. Simulations and experiments are used to demonstrate that the emitter performs visible and dual-band mid-infrared camouflage with thermal control management in two different application scenarios. First, the application to aircraft skin enables simultaneous infrared camouflage in two bands (low emissivity in atmospheric windows, \({\stackrel{-}{\epsilon }}_{3-5\mu m}=0.06\) and \({\stackrel{-}{\epsilon }}_{8-14\mu m}=0.01\)) and radiative cooling (high emissivity in non-atmospheric window, \({\stackrel{-}{\epsilon }}_{5-8\mu m}=0.68\)) as well as visual camouflage (low average reflectance of 0.21 in visible band). This selective infrared emission characteristic is preserved for incidence angles of radiated light ranging from 0° to 60°. Second, we combine the wavelength-selective emitter with insulating silica aerogel for application to the converging nozzle of aircraft, obtaining a reduction in the apparent temperature of the object from 873 K to approximately 313 K in detection ranges of 3–5 and 8–14 µm with and without earthshine. This in turn reduces the target detectable lock-on range by approximately 79% and provides an excellent infrared stealth effect. Moreover, the emitter has a simple structure and scalability, and provides convenience for mass production.