In order to solve phase change energy-saving technology applications in building envelope thermal design and improve indoor thermal comfort

experimental and theoretical studies about phase change component were carried out in this paper.The composite phase change component with different mass of phase change material was made of super-hemihydrate plaster and paraffin phase change material. DSC method was used to test phase change energy storage gypsum board's phase change temperature and phase change latent heat and steady-state test method was used to test thermal conductivity of different proportions of the component. Phase change heat transfer model was established and simplified. Heat transfer process and heat transfer mechanism of the component were analyzed. Solved by numerical simulation to study the effect of different proportions of phase change component in the Beijing area. Changing thermal conductivity and convective heat transfer coefficient respectively

application effects were studied for opotimization. The results show that along with the rising of the paraffin content

the thermal conductivity of phase change component minished. Among the four kinds ratio

component with 33% PCM had the best application effect in passive buildings in Beijng and in transition season its energy-saving amount was 10% more than that in traditional buildings. Enlarging thermal conductivity and convective heat transfer coefficient of phase change component can both improve indoor comfort and reduce energy consumption. The results of the research can provide a reference for building envelope thermal design with phase change material.