摘要
添加高热导率多孔骨架能够显著提高蓄热材料热导率,提升蓄热系统的蓄放热效率。本文对相变材料与梯度孔隙泡沫金属复合材料的热性能进行了数值研究。结果表明:相较于均匀孔隙结构,采用负梯度孔隙结构后,石蜡、Na2SO4·10H2O和Na2HPO4.12H2O三种相变材料的换热速率分别提升4.167%、8.333%和9.1%;平均蓄热速率分别提升4.35%、9.133%和10.02%.负梯度结构对换热效果的增强得益于其对靠近加热面的初始融化区域换热强度的显著提升,而正梯度结构削弱了该阶段换热强度。因此,梯度孔隙结构对相变换热的影响相较于均匀孔隙结构更强,并且对于不同相变材料这种影响程度有明显差异。
Adding porous framework with high thermal conductivity can significantly improve the thermal conductivity of phase change materials(PCMs),and enhance the thermal storage and release efficiency of the thermal storage system.In this study,the thermal properties of PCMs saturated into the graded metal foam were studied numerically.The results show that the heat transfer rates of paraffin,Na2SO4·10 H2O and Na2 HPO4·12 H2O increase by 4.167%,8.333%and 9.1%respectively,and the average heat storage rates increase by 4.35%,9.133%and 10.02%respectively.The enhancement of the negative gradient structure is due to the significant enhancement of the heat transfer intensity near the heating surface,while the positive gradient structure weakens the heat transfer intensity at this stage.Therefore,the effect of gradient porosity structure on the heat transfer of PCM is stronger than that of uniform porosity structure,and the effect on different phase change materials is obviously different.
作者
李宏阳
胡成志
唐大伟
LI Hong-Yang;HU Cheng-Zhi;TANG Da-Wei(Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education,School of Energy and Power Engineering,Dalian University of Technology,Dalian 116024,China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2020年第8期1984-1990,共7页
Journal of Engineering Thermophysics
基金
国家重点研发计划项目子课题(No.2016YFB0601601_02)
国家自然科学基金(No.51806028,No.51876027)
中央高校基本科研业务费(No.DUT19JC09,No.DUT17RC(3)043)。
关键词
相变储能
相变材料
梯度孔隙率
强化换热
有效导热系数
latent heat storage
phase change material
gradient porosity
enhancement of heat transfer
effective thermal conductivity
