A self-adjusting passive radiative cooling panel for spacecraft including a dielectric (e.g., HfO2) layer sandwiched between a mirror layer and spaced-apart thin-film phase-change (e.g., thermochromic) material islands disposed in a grating pattern having a lattice constant in the 2 to 10 μm range, depending on expected spacecraft operating temperatures. At low temperatures the phase-change material islands enter dielectric state phases that prevent generation of guided modes in the dielectric layer resulting in zero or low mid-IR emission. At high temperatures the phase-change material islands enter a metal state phase that couples mid-IR (thermal) radiation to guided mode resonances resulting in high mid-IR emission. The thermal emission can be tuned by the lattice constant of the grating pattern to peak at a target mid-IR wavelength (e.g., 8 μm), thereby significantly increasing the thermal emission contrast between the low and high temperature states resulting in the minimization of system-wide thermal transients.
Radiative Cooling Panels For Spacecraft
2017-10-19
Patent
Electronic Resource
English
IPC: | B64G Raumfahrt , COSMONAUTICS |