共查询到19条相似文献,搜索用时 62 毫秒
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固液相变蓄热技术的研究进展 总被引:4,自引:1,他引:4
综述了相变蓄热材料、相变传热问题求解方法、典型相变传热过程以及相变潜热蓄热系统(LHTES)优化设计及强化传热等诸多固液相变蓄热技术相关问题的研究进展情况 相似文献
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组合式相变材料贮能系统性能研究 总被引:1,自引:0,他引:1
本文主要研究由相变温度不同的相变材料(PCM)组合而成的贮能系统在给定温度边界条件下的循环工作性能,建立了相应的物理模型,给出了数值求解方法。数值计算结果表明,通过合理布置PCM的相变温度(PCT)分布,应用5 ̄10个PCM,可使系统相变时间减少27%左右;当每一个PCM都同时存在向同一方向移动而且移动速度相近的相界面时,系统相变时间最短。 相似文献
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用于墙体中的固-固相变材料储热性能的研究 总被引:3,自引:0,他引:3
使用固一固相变材料作为墙体中的储能材料不会发生渗漏.能增加墙体的蓄热能力,减小室内温度波动,减少建筑能耗。通过实验研究了多元醇类相变材料组成的二元体系在不同组成下的储热性能,从材料的相变温度和相变潜热分析其应用于墙体中的可行性。研究结果表明:在一定的组成下,多元醇二元体系可达到墙体储能要求的相变温度,且相变潜热较大,是理想的墙体相变储能材料。 相似文献
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物质在物相变化过程中由环境吸收热量或冷量,也可以向环境放出热量或冷量,以实现能量储存和释放.固-液相变储能过程具有较大的承压能力.利用海洋温差能驱动的水下滑翔机工作在几百米深的海水中,承受巨大的外界海水压力,选用固-液相变材料作为感温工质-储能材料,可以保证相变储能动力系统稳定可靠地工作.利用固-液相变储能机理运行的水下机器人即水下滑翔机,不需要自带能源而吸取海洋温差能获得驱动力.本文阐述相变储能机理,回顾相变储能研究的发展.以赤道附近海域为例,以水下热滑翔机相变换热管为分析对象,说明了固-液相变储能过程在水下运载器驱动上的应用. 相似文献
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总结近年来国内外相变储能材料的研究状况,包括相变储能材料的制备、传热性能、相变过程数值模拟和应用等,并对复合相变储能材料的传热性能研究方法的前景作了展望。 相似文献
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Application of energy storage enclosure with phase change materials in building energy saving 下载免费PDF全文
相变材料具有高效的能量储存功能。相变材料与建材基体结合,制成一种具有储热功能的围护结构。该围护结构可发挥相变储热功能,降低建筑室内温度波动,增强建筑热舒适度,能够更加有效地减少建筑物运行能耗,从而实现建筑节能。本文对当前现有相变材料的优缺点、相变材料在不同围护结构中的应用、相变储能围护结构对室内热环境的影响及对建筑运行能耗的影响、相变储能围护结构应用的经济性等方面进行了分析,提出相变储能围护结构在工程应用中所存在的不足及其发展前景。 相似文献
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Form-stable phase change materials for thermal energy storage 总被引:1,自引:0,他引:1
Murat M. Kenisarin Kamola M. Kenisarina 《Renewable & Sustainable Energy Reviews》2012,16(4):1999-2040
The present paper considers the state of investigations and developments in form-stable phase change materials for thermal energy storage. Paraffins, fatty acids and their blends, polyethylene glycol are widely used as latent heat storage component in developing form-stable materials while high-density polyethylene (HDPE), styrene-butadiene-styrene (SBS) triblock copolymer, Eudragit S, Eudragit E, poly (vynil chloride) (PVC), poly (vynil alcohol) (PVA) and polyurethane block copolymer serve as structure supporting component. A set of organic and metallo-organic materials with high transition heat in solid-solid state is considered as perspective for-stable materials to store thermal energy. Another perspective class of form-stable materials are the materials on the basis of such porous materials as expanded perlite and vermiculite impregnated with phase change heat storage materials. The technology of producing new form-stable ultrafine heat storage fibers is developed. It opens availability to produce the clothers with improved heat storage ability for extremely cold regions. The perspective fields of application of form-stable materials are discussed. The further directions of investigations and developments are considered. 相似文献
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Heat transfer behaviour of thermal energy storage components using composite phase change materials 下载免费PDF全文
对基于复合相变材料储热单元的储热性能进行了研究。建立了复合材料和储热单元体内部的二维传热模型,考察了复合材料物性和结构尺寸及传热流体操作条件(流体流速)对单元体储热性能的影响,对比了两种不同结构单元体的储热性能,并搭建实验平台进行了实验对比研究。对比结果表明,模型结果与实验结果趋于一致,验证了模型的准确性。复合材料物性和结构尺寸及传热流体操作条件对单元体储热性能有较大的影响。相比较单管储热单元体,同心管储热单元体有着更优的储热特性,在相同的操作条件下,同心管储热单元体的储热、放热时间较单管储热单元体分别减少10%和15%。 相似文献
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Experimental evaluations of manufactured samples of laminated and randomly mixed phase change material (PCM) drywalls have been carried out and compared with numerical results. The analysis showed that the laminated PCM drywall performed thermally better. Even though there was a maximum 3% deviation of the average experimental result from the numerical values, the laminated PCM board achieved about 55% of the phase change process as against 48% for the randomly distributed drywall sample. The laminated board sample also released about 27% more latent heat than the randomly distributed type at the optimum time of 90 min thus validating previous simulation study. Given the experimental conditions and assumptions the experiment has proved that it is feasible to develop the laminated PCM technique for enhancing and minimising multi‐dimensional heat transfers in drywall systems. Further practical developments are however encouraged to improve the overall level of heat transfer. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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In the present study, encapsulated phase change materials (PCMs) were used for the storage of thermal energy. Both experiments and simulation were performed to evaluate the characteristics of encapsulated PCMs. Tests were conducted in a packed bed to determine the performance of the encapsulated PCM. In the preparation of encapsulated PCMs, the coacervation technique was used. The performance of the encapsulated PCM was evaluated in terms of encapsulation ratio, hydrophilicity, and energy storage capacity. The experiments were designed, based on surface response method, to optimize the processing conditions. It was found that a higher coating to paraffin ratio led to a higher paraffin encapsulation ratio. The hydrophilicity value of encapsulated paraffin depended mainly on the ratio of paraffin to coating. The higher the ratio, the lower was its product hydrophilicity. When the paraffin to coating ratio was constant, the higher concentration of HCHO led to a lower hydrophilicity of the product. The encapsulated paraffin has shown large energy storage and release capacity (20–90 J g?1) during its phase changes depending on different ratios of paraffin to coating. Thermal cyclic test showed that encapsulated paraffin kept its geometrical profile and energy storage capacity even after 1000 cycles of operation. In the experiments and simulation of fluid heating process in encapsulated PCM charged packed bed, results showed that Eulerian granular multiphase model in FLUENT 4.47 is suitable for simulation of such a system. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献