| With the rapid development of economy,the contradiction between supply and demand of energy is becoming more and more prominent. People are engaged in developing massive conventional energy resources and searching for new alternative energy resources, at the same time the study for energy-efficient technology plays a significant role, too. Energy storage technology, as a part of energy-efficient technology, shows great potential in the proper allocation and utilization of energy. There are two ways for energy storage—sensible thermal storage and latent thermal storage, of which latent thermal storage technology catches great attention for its advantages such as the high energy storage density,constant phase change temperature, and so on. It can be widely applied in many fields like residual-heat utilization, solar energy utilization, electric power and buildings'air condition, etc.This study aims to prepare phase change materials (PCMs) which can improve building energy efficiency and find the way to examine the application effect of PCMs by adopting the method of combining experiment with simulation. Firstly,both present state and outlook of energy storage technology at home and abroad are introduced in this paper,and meanwhile the shortcomings of the current energy storage technology are discussed,too. In order to make the PCMs to have broader practical application, the researcher selects the more available materials such as Stearic Acid(SA),Lauric Acid(LA),Capric Acid(CA) as the raw materials of experiment. Next Differential Scanning Calorimeter(DSC) is used to test the phase-change temperature,the latent heat,and the specific heat of the three kinds of dual compound materials and the single material. Four kings of eutectic PCMs were prepared to adapt to the varied temperatures of different areas. Among them, the latent heat of the SA /CA composite is 149.3J/g; the latent heat of the LA/CA composite is 126.7J/g; and the latent heat of the SA/LA composite is 161.9J/g. A solidifying /melting experiment with the temperature ranging from 40℃to 15℃were conduct for testing the stability of PCM in the process of phase change, This experiment shows PCMs have very good stability. The researcher adopts porous media expanded perlite(EP) as carrier, and makes a compound of expanded perlite and PCM by directly immersing method in the liquid PCM. And the scanning electron microscope (SEM) shows that the PCM can fill the pore of the EP. The test shows that latent heat of the EP/PCM composite is 105.5 J/g, 74.41J/g and 96.2 J/g.For the sake of checking the practical applicability and popularizing of the PCM in building palisade structure,the researcher carries out application experiment in the model house with the prepared LA /CA eutectic material as PCM. According to the result of temperature test, adding the PCM has obvious effect on decreasing the fluctuation of temperature in the model house, the peak temperature is lower about 2℃than that the model house without PCM . And then on the base of the experiment,the FLUENT software is adopted to carry out numerical simulation for the tendency that the temperature field of wall inside with PCM and without PCM varies with the outside ambient temperature. The result of numerical simulation agrees quite well with that of experiment, error mainly appear in the process of phase change of the PCM, and the relative error does not exceed 2%. The building physics and mathematics model of the wall with PCM provide an important reference for future study which aims to examining the effects with the application of PCM in the wall palisade structure.
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