TY  - EJOU
AU  - Yu, Haiyan 
AU  - Li, Mingdong 
AU  - Guo, Ning 
AU  - Ren, Fengying 
AU  - Lu, Yongheng 
AU  - Du, Mu 

TI  - Effects of Wear-Induced Surface Roughness and Pore Taper on the Performance of Porous ZnS/Ag High-Temperature Solar Absorbers
T2  - Frontiers in Heat and Mass Transfer

PY  - 2025
VL  - 23
IS  - 5
SN  - 2151-8629

AB  - High-temperature radiative cooling is essential for solar absorbers, as it mitigates efficiency degradation resulting from thermal accumulation. While porous structures have proven effective in enhancing absorber performance, practical manufacturing processes and prolonged operational wear inevitably introduce surface roughness and structural deviations, which profoundly impact radiative properties. This study constructs a ZnS/Ag solar absorber model with surface roughness and employs the finite-difference time-domain method to investigate how characteristic length, surface roughness, porosity, pore shape factor, and taper influence its radiative properties in the 3 μm–5 μm band at 750 K. Results show optimal absorption at a 1 μm characteristic length with a 36.72% improvement compared to the model with <i>l</i> = 0.25 μm, increased absorption with higher porosity with a 69.29% improvement at 0.6 compared to the non-porous structure, lower circularity with a 19.03% improvement for <i>C</i> = 0.89 compared to <i>C</i> = 1.00, while surface roughness with a 61.24% improvement at <i>RMS</i> = 0.031 compared to <i>RMS</i> = 0 and taper with a 38.29% improvement at <i>β</i> = 20° compared to <i>β</i> = 0° also exert significant effects. This work provides engineering design guidelines for high-efficiency, low-cost absorbers.
KW  - Radiative cooling; surface roughness; porous materials; optical properties; solar thermal conversion

DO  - 10.32604/fhmt.2025.071263