Influence of External Surface Radiation Properties on Thermal Performance of Walls-Take a typical office building in Chengdu as an example

Abstract

In this paper, taking a typical office building in Chengdu as an example, the coupling relationship between the radiation properties (short-wave absorption coefficient and long-wave emission coefficient) of the external surface materials of the wall and the insulation types and the insulation performance is studied by using software simulation method. The results show that the internal insulation wall is beneficial to reduce the heating load while the external insulation wall is beneficial to reduce the cooling load. And the external surface material's radiative properties hardly affect the wall insulation type choice. Still, in the case of Chengdu office buildings, interior insulated walls are more conducive to year-round building energy efficiency. In summer, the radiation characteristics of the outer surface material will affect the choice of the best heat transfer coefficient (U-value) of the wall. When the short-wave radiation absorption coefficient is small, the wall with good insulation performance will appear anti-energy-saving phenomenon. Therefore, it is recommended that the regions with high cooling loads fully consider the influence of the external surface material's radiation properties on the wall's thermal performance in the design of the thermal performance of the wall.