基于纳米复合PCM集蓄热构件的建筑太阳能供暖特性研究

Study on heating characteristics of building based on nano-composite PCM solar collection and storage components

设计一种基于吸光型纳米复合相变材料(PCM)模块化集蓄热构件,将其应用于建筑太阳能采暖,以降低能耗和碳排放。开展石墨烯-石蜡复合相变材料的制备和物性测试,建立PCM集蓄热数学模型,并结合典型气候工况进行供热特性的数值模拟,研究定风量情况下蓄热层厚度和空气流道宽度对供暖特性的影响,分析通风速度对送风温度、日供热量以及太阳能供暖保证率的影响。研究结果表明:添加石墨烯后的纳米复合PCM相对于纯石蜡的集热效率约提升了60%;对于具有18 m^(2)采光面积的集蓄热构件,当通风速度为1.0 m/s时,太阳能集蓄热墙具有较为优异的供暖性能,此时供给室内的日供热量、日平均热效率和供暖保证率分别为112.5 MJ、67.6%和90.0%,室内能够达到20℃的设定温度的时间为13 h。

A modular solar collection and storage component based on absorbable nanocomposite phase change material(PCM)was designed and applied to building solar heating systems to reduce building energy consumption.The preparation and physical property tests of graphene-paraffin composite PCM were carried out,the PCM solar storage mathematical model was established,and the numerical simulation of heating characteristics was carried out in combination with typical climatic conditions.The effect of heat storage layer thickness and air flow channel width on heating characteristics under constant air volume condition was studied.The influence of ventilation speed on air supply temperature,daily heat supply and solar heating guarantee rate was analyzed.The results show that the heat collection efficiency of the nanocomposite PCM added with graphene increases by about 60% compared to that of the pure paraffin wax. For a solar thermal storage component with a lighting area of 18 m^(2), when the ventilation speed is 1.0 m/s, the solar thermal storage wall exhibits excellent heating performance. At this time, daily heat supply for indoor use, average daily heat efficiency, and heating guarantee rate are 112.5 MJ, 67.6% and 90.0%, respectively. The duration of indoor temperature reaching the set temperature of 20 ℃ is 13 h.