An Efficient Optimization Strategy Applied to Spacecraft Smart Radiation Devices Design

Smart radiation devices (SRDs) for spacecraft, which utilize thermochromic films with adaptive emissivity switching capability and minimal resource consumption, have garnered attention. However, there remains a lack of systematic strategies for more efficient SRDs design. In this study, we focus on a typical SRD, namely VO2/ BaF2/Ag, to exemplify and investigate two optimization methods: the quarter-wave condition and the traversal method. By employing the quarter-wave condition, the intermediate dielectric layer thickness required to induce Fabry-Perot resonance is determined as 1.81 mu m. In this case, the emission modulation is 0.62, and the solar absorption is 0.29. However, utilizing the traversal method, optimized thicknesses for VO2 and BaF2 are found to be 0.02 mu m and 1.60 mu m, respectively. It is found that the emission modulation can reach 0.64, while the solar absorption remains unchanged at 0.29. Notably, the traversal method yields superior emission modulation of SRD compared to the quarter-wave condition, while there is no difference in solar absorption of SRD obtained by the two optimization methods. Consequently, the quarter-wave condition can provide an approximate range for the thickness of the dielectric layer in SRD designs, with further optimization achieved through the traversal method to enhance SRD performance. Overall, our research supplies valuable theoretical guidance for SRD design and aims to propel advancements in spacecraft thermal control.