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Películas de refrigeración radiativa de alta conductividad térmica para un enfriamiento pasivo mejorado durante el
Shijin Nie1, Lizhan Bai1, Guiping Lin1,2
1Laboratory of Fundamental Science on Ergonomics and Environmental Control, School of Aeronautic Science and Engineering, Beihang University, Beijing 100191, P. R. China.
ACS applied materials & interfaces
|August 27, 2025
Resumen
Este estudio introduce una nueva película de refrigeración radiativa (película DPHA) que mejora la eficiencia de refrigeración mediante la integración de canales térmicos internos. La película DPHA demuestra un rendimiento superior, ofreciendo una diferencia de temperatura significativa para aplicaciones de enfriamiento radiativo pasivo durante el día.
Área de la Ciencia:
- Ciencias de los materiales
- La termodinámica
- Energía sostenible
Sus antecedentes:
- El enfriamiento radiativo pasivo diurno (PDRC) ofrece refrigeración que ahorra energía al reflejar la luz solar y emitir calor.
- El PDRC práctico está limitado por la irreversibilidad del flujo de calor, lo que dificulta el máximo potencial de enfriamiento.
- El desarrollo de materiales de refrigeración radiativa avanzados es crucial para una gestión térmica eficiente.
Objetivo del estudio:
- Desarrollar una película de refrigeración radiativa (RC) integrada con alta conductividad térmica para mejorar el rendimiento de refrigeración.
- Superar las limitaciones de los materiales de enfriamiento radiativo convencionales mediante la mejora de la disipación del calor.
- Evaluar las propiedades ópticas, la conductividad térmica y la durabilidad de la nueva película RC.
Principales métodos:
- Fabricación de una película de refrigeración radiativa integrada (película DPHA) con canales térmicos internos.
- Caracterización de las propiedades ópticas, incluida la reflectividad solar y la emisividad infrarroja.
- Medición de la diferencia de temperatura bajo la irradiación solar y evaluación de la conductividad térmica.
- Evaluación de la resistencia al envejecimiento bajo irradiación UV continua.
Principales resultados:
- La película DPHA alcanzó propiedades ópticas superiores (reflectividad ~ 0,96, emisividad ~ 0,98).
- Se registró una diferencia de temperatura máxima de 17,5 °C y un promedio de 13,2 °C bajo una intensidad solar de 977 W m−2.
- La película exhibió una alta conductividad térmica fuera del plano (0,755 W m-1 K-1), lo que facilitó una disipación de calor eficiente.
- La película DPHA demostró excelentes propiedades ópticas y resistencia al envejecimiento después de 30 días de exposición a los rayos UV.
Conclusiones:
- La película DPHA desarrollada mejora significativamente el rendimiento de enfriamiento radiativo a través de una mayor conductividad térmica y propiedades ópticas optimizadas.
- La película muestra un gran potencial para aplicaciones de refrigeración al aire libre escalables y rentables.
- Este trabajo presenta un nuevo enfoque para el desarrollo de materiales de refrigeración radiativa de alto rendimiento.
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