Fig. 1. Schematic of the particle-composite coating stacked with thermal protection layer

Fig. 2. Apparent spectral emissivity of the composite coating obtained by simulations of varying domain width, the volume fraction of the embedded particles is 10% and the particle diameter is 0.2 μm

Fig. 3. Apparent spectral emissivity of the composite coating obtained by simulations of varying mesh size, the volume fraction of the embedded particles is 10% and the particle diameter is 0.2 μm

Fig. 4. Complex refractive index of the thermal protection layer material: (a) YSZ; (b) SiO₂ aerogel

Fig. 5. Apparent spectral emissivity of the composite coating with different thicknesses of YSZ and SiO₂ aerogel thermal protection layers

Fig. 6. Variation of the apparent average emissivity of the composite coating with the thickness of (a) YSZ and (b) SiO₂ aerogel thermal protection layer

Fig. 7. Variation of the apparent average emissivity of the composite coating with different embedded-particle sizes with the thickness of (a) YSZ and (b) SiO₂ aerogel thermal protection layer

Fig. 8. Variation of the apparent average emissivity of the composite coating with different embedded-particle volume fractions with the thickness of (a) YSZ and (b) SiO₂ aerogel thermal protection layer

Fig. 9. Variation of the apparent average emissivity of the composite coating in 3-5 μm and 8-14 μm with the thickness of non-absorbing thermal protection layer of different refractive index

Fig. 10. Variation of the apparent average emissivity of the composite coating in 3-5 μm and 8-14 μm with the thickness of the thermal protection layer of different absorption coefficients

Fig. 11. Power absorption density distribution in the thermal protection layers of different thicknesses. The wavelength is 9 μm, and the complex refractive index is n=2, k=0.1

Fig. 12. Power absorption density distribution in the thermal protection layers of different absorption coefficients. The wavelength is 9 μm and the thickness of the thermal protection layer is 10 μm