Design and Analysis of Low Emissivity Radiative Cooling Multilayer Films Based on Effective Medium Theory

Haiyan Yu

Haochun Zhang Email

Zanen Dai

Xinlin Xia

School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, China

Abstract

Radiative cooling films are energy-efficient devices widely used in several domestic and industrial applications. To broaden its application in systems that require higher temperature requirements, this study designed low emissivity multilayer films using effective medium theory. The multilayer films obtained reflectivity greater than 0.99 at temperature regions of 207-362K, 580-960K and 1159-1932K. Combination of these basic films resulted in the bottom layer being significantly impacted upon during cooling radiation. Furthermore, the radiative cooling films with 6 periods, high refractive index ratio, and 0.014 μm root mean squared roughness achieved the optimal application effect and economic benefits.

Design and Analysis of Low Emissivity Radiative Cooling Multilayer Films Based on Effective Medium Theory