Building envelopes with radiative cooling materials: A model for indoor thermal environment assessment based on climate adaptation

Abstract

To create a comfortable thermal environment in buildings, building cooling account for a large part of building energy consumption in summer. The spectral radiative properties of radiant cooling materials as a passive cooling technology have been extensively studied. However, there are few studies that address the application of radiant cooling materials to building envelopes. This paper proposed a radiative cooling glass composite structure for windows based on existing radiant cooling materials and established a climate adaptive radiant cooling building indoor thermal environment assessment model. This assessment model combines the spectral selectivity of radiative cooling materials with climate characteristics. An indoor thermal environment test system and an ambient climate measurement system are designed under the influence of external windows, and the average error of the assessment model is verified to be no more than 4.83%. Based on this assessment model, three applicability analyses were conducted: Firstly, it is concluded that the daytime indoor temperature with radiative cooling glass (RCG) is 26.43°C lower than that with the ordinary glass. Secondly, RCG can effectively improve the indoor thermal environment for rooms facing each direction, and the indoor temperature is 45.06°C lower than that of ordinary glass in the east and west directions, and 15.05°C lower than that of ordinary glass in the north and south directions. Finally, analysis of the correlation between indoor temperature and outdoor temperature shows that the indoor temperature tends to rise as the outdoor temperature rises. The analysis of the application of RCG in different cities shows that the performance of radiative cooling is relatively weak in areas with high relative humidity.