【作者】 陈志锋；

【导师】 唐志伟；

【作者基本信息】 北京工业大学 ， 热能工程， 2007， 硕士

【摘要】 当今的能源危机和环境污染已成为社会发展所面临的两大难题,开发利用可再生能源、能源的循环再利用和节能环保等具有同等重要的现实意义。蓄能技术可以有效地提高能源的利用效率。由于能源的孕育、开发、生产和应用有很强的时间依赖性,所以可以利用蓄能技术,把供大于求时的能量储存起来,供需要时使用,这样既可以提高能源的利用率也可以缓解能源利用的紧迫性。以相变蓄热为主,它将能量以热能的形式储存起来供需要时使用。所以相变蓄热技术可以解决热能供给与需求失衡的矛盾,在太阳能利用、电力的“移峰填谷”、废热和余热的回收利用、工业与民用建筑供暖和空调的节能以及航空航天、纺织工业等领域具有广泛的应用前景。因此,相变蓄热技术作为一种能量存储的新技术,在节能领域已经引起学术界和工业界的广泛关注。但是相变蓄热材料作为一种新式的能源利用形式,由于本身具有过冷、析出和导热系数低等缺点以及从其使用的经济性方面考虑,都是其未获得广泛推广和应用的原因所在。本文针对相变材料本身的缺点加以利用和改进,并结合化学热力学及生理卫生学方面的知识,从改变人类传统被动式御寒保暖方式,转向主动变热调温的方式为出发点,研究并探讨了用相变材料(PCM)试制智能“相变蓄热垫”的性能.课题内容分两大方面:一是材料的选择;另一方面是“相变蓄热垫”的设计及调温性能测试.首先,对相变蓄热材料的应用进行了介绍,并对多种相变材料的分析,通过对材料在DSC检测的基础上,根据相变温度和潜热大小的比较,最终确定了硬脂酸和十二水磷酸氢二钠作为本课题的选择材料。本文通过对硬脂酸和十二水磷酸氢二钠两种材料的物理化学性质及其相互的作用关系研究,大胆的选用了以上两种材料的二元混合物作为相变蓄热垫的蓄热材料,通过大量实验证明硬脂酸和十二水磷酸氢二钠两种相互混合,可以克服本身各自的缺点,由于硬脂酸和十二水磷酸氢二钠具有相同的晶体结构,所以混合物中硬脂酸可以起到十二水磷酸氢二钠的成核剂的作用。同时,十二水磷酸氢二钠也可以相对的起到提高硬脂酸的导热性能。并通过红外光谱分析得出,两种材料属于物理混合,混合对其本身具有的高潜热值没有带来影响。在对材料性质的分析后,本文还对材料进行了包装、加热到成型设计。通过大量实验,测试样品在不同环境,静态情况下的加热、保暖性能,并对材料的稳定性进行分析,实验结果表明,硬脂酸和十二水磷酸氢二钠混合作为相变蓄热垫效果达到了预想的效果,具有一定的市场开发价值。更多还原

【Abstract】 Nowadays, energy crisis and environmental pollution become more and more serious. It has become two important problems in social development. It is of necessary to develop and use renewable energy as well as take measure on environment protection and energy conservation.Energy storage technology can greatly improve energy utilization efficiency. Energy generation, exploitation, production and adoption have great time dependence, so we can use energy storage technology to improve the energy utilization efficiency and reduce the pressure of energy utilization. When the energy supply exceeds the need, we can use the technology to store the surplus, and release it at requested. Take phase-change thermal storage for instance, it will translate energy into heat energy, and store it for future use. So the technology of phase-change thermal storage can solve the contradiction of the balance of thermal energy’s supply and demand. Phase-change thermal storage technology has promising prospect in solar energy utilization, peak-load shifting, reutilization of waste heat and exhaust heat, energy conservation in heating and air condition of industrial and agricultural architectures, aircraft and spacecraft, as well as in textile industry and so on. Now phase-change thermal storage technology has drawn the attention of the academia and industry as a new technology in saving energy.As a new form of energy utilization, however, phase-change thermal storage material itself has a lot of shortcoming such as overcooling precipitation, low thermal conductivity, and economical aspect etc. So it is why phase-change thermal storage technology isn’t widely promoted and effectively applied.This paper aims at making use of and improving the disadvantages of phase changing materials. And combined with the knowledge of chemistry, thermodynamics and physiologic and hygiene, this paper studies and discusses the performance of trial-producing“phase-change thermal storage cushion”made by phase changing materials(PCM) by the way of keeping warm from traditional passive to actively adjusting temperature. There are two parts of contents for this research: one is the choice of materials; the other is designing and testing performance of the“phase-change thermal storage cushion”. Firstly, presents the application of the phase changing materials and analyzes many kinds of materials. According to the phase changing temperature and latent heat based on DCS testing, stearic acid and NaH2OPO312H2O are chosen to as this paper’s trial materials.This text studies the physical and chemical properties of stearic acid and NaH2OPO312H2O and their mutual action each other. Finally, the binary mixture of the two kinds of materials was chose to make up the phase-change thermal storage cushion. After abundant experiment, it is approved that the disadvantages of these two materials respectively can be got over when the two materials are mixed. Stearic acid in the mixture can be regard as nucleating agent because they have the same crystal structure. Meanwhile, the performance of heating conduction of stearic acid can be advanced due to the action of NaH2OPO312H2O. After analyzing the infrared spectrum, it can be concluded that two kinds of materials are physical mixing, as a result there are no effects on their high latent heating.The materials are packed, heating and forming design after analyzing the properties of these materials. Test the performance of heating and keeping warm of samples under different conditions by a great deal of experiment. Furthermore, analyze the stabilization of materials. The experimental results show good agreement with predicted effects. Therefore, there is meaning of market development.更多还原