陶瓷-熔融盐复合相变储能材料

摘要

This paper reports a study on ceramic based phase change materials (PCM).Sodium nitrate (NaNO3) was used as the PCM,magnesium oxide (MgO) as the ceramic matrix,and different types of carbon materials as the thermal conductivity enhancers (TCE).The composites were fabricated by mixing,compaction,and sintering.The effect of carbon material addition was studied and the morphological and thermophysical properties of the composites were characterized.The results showed that the addition of the TCE could either hinder or enhance the thermal diffusivity of the composites,depending on the type of TCE used.It was found that the thermal energy storage density increased with increasing PCM concentration in the composite.All the composites manufactured were found to be thermally stable up to 500 ℃.%研究了石墨材料包括纳米石墨对基于硝酸盐陶瓷复合相变储热材料性能的影响.其目的在于制备一种可用于集中式太阳能热发电(CSP)和工业废热回收(IWH)等应用的新型高温复合相变材料,并且使用导热增强物质(TCE)提升相变材料的导热性能.复合相变储热材料主要由硝酸钠(NaNO3)相变材料,氧化镁(MgO)陶瓷基体,以及不同种类、不同比例的石墨导热增强剂组成.通过对复合材料的形态及热物理性质测定表明:不同种类的石墨导热增强剂对复合材料的导热性能影响不同,复合材料的储热密度随复合材料中相变材料比例的增加而增加.所得基于硝酸盐的陶瓷复合材料均可在500℃保持良好的热稳定性,因此其潜在应用包括工业废热回收及集中式太阳能热发电系统(CSP)等.