用于地板辐射采暖的多元水合盐复合相变砂浆的制备及性能研究  

Preparation and thermal storage performance study of multivalent hydrated salt composite phase change mortar for floor radiant heating

作　　者：刘洁 杨英英 李爱征 王文松 任燕 LIU Jie;YANG Yingying;LI Aizheng;WANG Wensong;REN Yan(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《储能科学与技术》2023年第12期3655-3662,共8页Energy Storage Science and Technology

基　　金：国家自然科学基金项目(52006146)。

摘　　要：本研究以地板辐射采暖为应用背景,Na_(2)HPO_(4)·12H_(2)O和Na_(2)SO_(4)·10H_(2)O为原料,研发出一种新型无机水合盐复合相变砂浆。首先,采用物理共混法制备出二元混合熔融盐(80%Na_(2)HPO_(4)·12H_(2)O-20%Na_(2)SO_(4)·10H_(2)O),并通过添加成核剂(2%Na_(2)SiO_(3)·9H_(2)O)优化其过冷度;然后,选择2~2.5 mm的膨胀珍珠岩对其进行吸附封装,得到定型复合相变材料;最后,将定型复合相变材料掺入砂浆中制备出复合相变砂浆。通过差示扫描量热法(DSC)测试,获得二元混合熔融盐、二元共晶盐和定型复合相变材料的相变焓值分别为229.1 J/g、214.1 J/g和156.7 J/g,通过电子扫描显微镜(SEM)对定型复合相变材料进行表征,发现膨胀珍珠岩与共晶盐相变材料相容性良好。所制备的复合相变砂浆的导热系数为0.63 W/(m·K),固态比热容和液态比热容分别为1.56 J/(g·K)和1.75 J/(g·K),传热系数为3.85 W/(m^(2)·K)。对复合相变砂浆进行了储热性能试验,发现与普通砂浆相比,复合相变砂浆可以更明显地减缓温度波动。在50℃恒温加热时,其冷端峰值温度比普通砂浆低2.5℃,在冷却时,其温度下降速率更小,说明复合相变砂浆具有良好的储热能力。将所制备的复合相变砂浆应用到间歇性地板辐射采暖中,可以在供暖时进行储热,使室内温度不至于过高,同时在停止供暖时释放热量,减缓室内温度降低速率,避免室内温度过低。复合相变砂浆的使用,能够在满足室内热舒适的同时抑制室内温度波动,实现热量的“移峰填谷”,减少供暖能耗,从而达到建筑节能的目的。This study focuses on the development and evaluation of a novel inorganic hydrated salt composite phase change mortar for radiant floor heating,utilizing Na_(2)HPO_(4)·12H_(2)O and Na_(2)SO_(4)·10H_(2)O as primary raw materials.The fabrication process involved the preparation of binary mixed molten salt(80%Na_(2)HPO_(4)·12H_(2)O-20%Na_(2)SO_(4)·10H_(2)O) through a physical blending method,adding a nucleating agent(2%Na_(2)SiO_(3)·9H_(2)O) to optimize subcooling.To enhance adsorption and encapsulation,expanded perlite particles(2—2.5 mm) were integrated,resulting in the formation of a stereotyped composite phase change material.This material was seamlessly integrated into the mortar matrix to create the composite phase change mortar.Differential scanning calorimetry tests were conducted on binary molten and binary eutectic salts,as well as stereotyped composite phase change materials,yielding enthalpies of phase change at 229.1,214.1,and 156.7 J/g,respectively.Scanning electron microscopy revealed excellent compatibility between expanded perlite and eutectic salt phase change materials in the microstructure of the stereotyped composite phase change material.Thermal properties of the developed composite phase change mortar are as follows:0.63 W/(m·K) thermal conductivity,1.56 and 1.75 J/(g·K)specific heat capacity in solid and liquid states,and 3.85 W/(m^(2)·K) heat transfer coefficient.To assess the practical impact of the composite phase change mortar,heat storage performance was tested.Comparative analysis with standard mortar demonstrated that the composite phase change mortar significantly mitigates temperature fluctuations.During the heating test with a hot plate at 50 ℃,the peak temperature of the composite phase change mortar at the cold end remained 2.5 ℃ lower than standard mortar.Additionally,the composite phase change mortar exhibited a gradual temperature rate decrease during cooling,indicating robust heat storage capabilities.When applied to intermittent radiant floor heating,the composi

关 键 词：无机水合盐 相变材料 砂浆 储热 地板辐射采暖 

分 类 号：TK02[动力工程及工程热物理]