Investigation of asymmetric optical properties in three-layer polyethylene-ceramic composite films for enhanced solar drying efficiency.
Annotatsiya
This study presents the development and spectral characterization of an asymmetric three-layer polyethylene (PE) composite film integrated with ceramic granules for solar drying applications. The primary objective was to investigate the influence of ceramic layer orientation on the optical transmittance, reflectance, and absorption properties within the UV-Vis-NIR range 300–1100 nm. Experimental results revealed that the composite film exhibits significant optical asymmetry compared to pristine PE. When correctly oriented (ceramic layer facing the product), the film demonstrates superior UV-blocking (reduction from 82.4 to 12.6%) and enhanced NIR absorption, facilitating the generation of pulsed infrared radiation. Conversely, reverse orientation significantly diminishes these effects due to increased surface reflection and thermal leakage. The findings confirm that the 3-layer asymmetric structure acts as a ’photonic valve,’ optimizing solar energy harvesting and thermal conversion. This research provides a technical foundation for utilizing directionally-active composite films to improve the efficiency and quality of solar-based food dehydration processes.