【作者】 钟世民；

【导师】 王昭俊；

【作者基本信息】 哈尔滨工业大学 ， 供热、供燃气、通风及空调工程， 2010， 硕士

【摘要】 随着科学技术的发展和人们生活水平的提高,能源供需在时间上的失配现象越来越严重。为解决此能源矛盾,相变储能技术应运而生。相变储能技术是利用物质在相变过程中吸收或释放能量以达到能源供需匹配的技术。可应用于暖通空调系统中的相变储能材料多在低温范围内,因此研究低温范围内相变储能材料对于解决能源问题意义重大。而低温范围内的最佳相变材料为有机脂酸类和结晶水合盐类两种材料。首先,利用温度曲线法对癸酸—月桂酸二元体系进行了实验研究,得出了该二元混合物的相变温度曲线。基于实验数据和理论数据,得出该二元混合物存在低共熔点,当癸酸占该二元混合物的质量为66%~70%时,低共熔温度约为19℃~20℃。并通过添加石墨粉对其导热性能进行了改善,但是由于石墨粉的密度大于脂肪酸而沉淀,导致导热性能提高较小。其次,对钾明矾进行了成核剂添加量的实验,从而找出了使钾明矾相变温度在70℃左右且过冷度较小的最优成核剂添加量。并通过温度曲线法和DSC方法对钾明矾多次循环熔冻后的相变温度、过冷度和相变潜热进行了研究,验证了其稳定性能。通过添加石墨粉来改善钾明矾导热性能的实验,发现石墨粉的添加只是物理混合,随着石墨粉添加量的增加,导热性能也在增加。第三,根据现有的应用成果,提出了本课题相变储能材料在暖通空调系统中的应用思路。基于以上研究成果,可为该低温相变储能材料在暖通空调系统中的应用提供必要的实验数据和技术支撑。更多还原

【Abstract】 With the development of science and technology and the improvement of people’s life, the mismatch of energy supply and demand is becoming more and more serious. In order to overcome the mismatch, the energy storage technology with phase change emerged. During the process of phase change, the materials can absorb or release energy, which can match the energy supply and demand.Materials for energy storage used in HVAC systems have the phase transition temperature range in low-temperature range, therefore, it’s significant to study the low-temperature PCMs to solve the energy problem. fatty acids and hydrated salts usually are the ideal candidates for the low-temperature energy storage system.First, the phase transition temperature curve of the binary mixture was obtained through the experimental investigation to capric acid and lauric acid by T-history method. Based on the experimental data and theoretical data, the eutectic melting point is between 19℃~20℃, when the proportion of capric acid is between 0.66~0.7.We also studied on their thermal conductivity improvement by adding graphite powder.Second, the optimal amount of nucleating agent for aluminum potassium sulfate was found by the experimental investigation. The research on phase transition temperature, the degree of supercooling and latent heat after thermal cycles was carried on by T-history method and DSC method. At the same time, the thermal conductivity improvement experiment of aluminum potassium sulfate by adding graphite powder was carried on, and the results showed that the addition of graphite powder id mechanically mixed, and with the increase of the amount of graphite powder, the thermal conductivity increases.Finally, based on the existing applications, some improvements were put forward to. The production resulted from the above experimental researches will provide the necessary experimental data and technical support for the application in HVAC systems.更多还原