CAJ | 학술논문

相变材料的低热导率是限制潜热蓄热广泛应用的重要原因。将相变材料石蜡真空条件下注入到泡沫金属铜内制备泡沫金属铜-石蜡复合相变材料，通过铜的高热导率及高孔隙材料的大面体比来强化相变换热过程。采用DSC 示差扫描量热法对石蜡进行热物性测量获得准确的石蜡相变温度及相变潜热。以管壳式相变蓄热结构为对象，提取对称结构进行可视化设计，对比纯石蜡及泡沫金属铜-石蜡复合材料在相同运行条件下的相变过程，追踪二者熔化过程的相界面位置随时间的演化过程并布置热电偶准确测量材料内部的温度分布。结果显示加入泡沫金属后的复合材料的内部温差明显减小，温度分布均匀，蓄热热通量显著增大，有效缩短相变时间并缓解了自然对流造成的顶部过热和底部不熔化现象。
상변재료적저열도솔시한제잠열축열엄범응용적중요원인。장상변재료석사진공조건하주입도포말금속동내제비포말금속동-석사복합상변재료，통과동적고열도솔급고공극재료적대면체비래강화상변환열과정。채용DSC 시차소묘량열법대석사진행열물성측량획득준학적석사상변온도급상변잠열。이관각식상변축열결구위대상，제취대칭결구진행가시화설계，대비순석사급포말금속동-석사복합재료재상동운행조건하적상변과정，추종이자용화과정적상계면위치수시간적연화과정병포치열전우준학측량재료내부적온도분포。결과현시가입포말금속후적복합재료적내부온차명현감소，온도분포균균，축열열통량현저증대，유효축단상변시간병완해료자연대류조성적정부과열화저부불용화현상。
Latent heat thermal energy storage technology is a promising option for future cost reduction in parabolic trough power system, however, low thermal conductivity of phase change material (PCM) is the major shortage leading to large temperature difference between heat transfer surface and solid-liquid interface of the PCM, and low energy storage rate. A charging experimental system was set up for testing the dynamic thermal behavior of phase change material in metal foam. Paraffin wax is used as PCM and its thermal properties were determined with differential scanning calorimetry (DSC). Metal foam was made of red copper. The sample of PCM-foam composite with semi-circular slot was placed inside a transparent cuboid Plexiglas enclosure, and a copper tube with the same radius as the semi-circular slot was in close bonding with the PCM-foam composite. High temperature water flowed through the copper tube as the heat transfer fluid (HTF) heating the composite material. The temperature field and melting process of PCM at pore size were studied using appropriate thermocouple and high definition camera. Thermal characteristics, including temperature profiles and position of solid/liquid interface were investigated and recorded, and the effects of heating temperature and flow rate of HTF on temperature uniformity and melting rate were documented and discussed. Metal foam could effectively improve heat transfer performance of PCM and decrease charging time Temperature difference was smaller and heating flux was larger in the composite than those in pure paraffin.