Numerical Simulation Of Phase Change Thermal Storage System Of Aluminum Alloy At High-temperature

Solar energy is a huge treasure of power source because it's clean and pollution-free and it can be gotten conveniently. However, the use of solar energy is restricted by the impact of geography, day and night, seasonal changes, weather and other random factors. In order to maintain the stability of the heating or power supply uninterrupted operation, thermal storage technology has attracted increasing attention. With high energy storage density and lower degree of supercooling, metal-based phase change materials has a wide range of application in high-temperature thermal storage. It also has advantages of high thermal conductivity and long-term stability after repetitive phase-change as well as easy process control.Combined with existing research and based on the high-temperature solar thermal power generation system for the temperature of 400-800℃, a series of Al-Si alloy were chosen as the object of study in this thesis. The thermal properties such as microstructure, density, phase change temperature, latent heat of phase change and other performance were studied with the help of metallographic technique and integrated thermal analysis. Al-Si alloy eutectic composition has the highest latent heat about 450J/g among the Al-Si series aluminium alloy thermal storage materials which have higher phase change latent heat than others.Based on the design of Thermal Storage System, 2D and 3D finite element model of Thermal Storage Room were established and the numerical simulations of the insulation performance were analyzed and followed with the comparison of the analyse results of 2D and 3D model. On the other hand, the 3D finite element model of thermal storage unit composed of steel pipe with Al-Si alloy in it was established. The numerical simulation results of the transient analysis were also studied.The ANSYS secondary development was accomplished with Visual Basic6.0 based on the analysis results of the insulation performance. The program module, from which the parameters can be modified and the ANSYS program can be directly called was gained. With the help of the module, the analyse results of different Parameters were compared. The research shows: the Al-Si alloy has great prospects in high-temperature solar thermal storage for its high density of thermal storage and high latent heat. The numerical simulation of the insulation performance has assisted the structural design of the Thermal storage room as the analyse results closely match the theoretical calculations. Only need modifying the parameters of one kind of material can it obtains the analyse results of other materials by using the program module secondary-developed with VB can call the ANSYS from outside.The research in this thesis has laid a foundation for the following simulation and establishment of the thermal storage room. The thermal storage system and the secondary development module have great potential for development.