The Research On Heat Storage Performance And Practical Application Of Aluminum-based High Temperature Phase Change Thermal Storage Material

Abstract:With the research and application of solar thermal power technology is worldwide, the research on the property and application of the high-temperature phase change thermal storage materials has attracted increasing attention. In this thesis, on the basis of Al-Si alloy, we optimize the design and prepare nine aluminum high-temperature phase change thermal energy storage materials with different components. With the help of X-ray diffraction(XRD), scanning electron microscope(SEM), differential scanning calorimetry (DSC) and other modern analytical tools, the microstructure, phase change temperature, latent heat, sensible heat, and total energy storage and other properties of these phase change thermal energy storage materials were studied. The main conclusions are as follows:(1) The phase change temperature of aluminum alloy phase change thermal storage materials we have designed and prepared range between400～800℃, the latent heat of all aluminum alloys are higher than200J/g and can meet the requirements. Al-Si series aluminum alloys have higher latent heat, about to400J/g.(2) Al-Cu-Mg-Zn series aluminum alloy have higher density and thermal conductivity compared to the Al-Si series and Al-Cu-Mg-Si series aluminum alloy phase change thermal storage materials, and have a total thermal storage above3200J/cm3, more suitable for solar thermal power generation system.(3) The oxidation weight-gain of Al-Cu-Mg-Zn series aluminum alloys increase with the oxidation time increase at the same temperature under high temperature oxidation; in the case of the same oxidation time, as the oxidation temperature increases, oxidation weight-gain increased significantly.(4) Al-Cu-Mg-Zn series aluminum alloys do not substantially oxidized or that an oxide film is formed on the sample surface, preventing the sample continued oxidation at lower temperature; but at higher temperature, with the oxidation time increasing, the oxide film formed on the surface of the sample has been destroyed and broken, and can not prevent the oxidation of the sample.(5) The phase change latent heat of Al-Si series aluminum alloys have a small amount of decline with the increase of the number of thermal cycles, but the decline is very small and under3.84%; The phase change temperature of Al-Si series aluminum alloys have a small amount of increase with the increase of the number of thermal cycles, but the change are very small and under0.31%.