十二水磷酸氢二钠复合相变材料制备及应用于大棚降温的节能效果  

Preparation and energy-saving effects of disodium hydrogen phosphate dodecahydrate composite phase-change material applied in greenhouse cooling

作　　者：肖强强 孙佳康 唐洪达 张林华[1] 刁乃仁 李辉 XIAO Qiangqiang;SUN Jiakang;TANG Hongda;ZHANG Linhua;DIAO Nairen;LI Hui(School of Thermal Engineering,Shandong Jianzhu University;Shandong Zhongrui New Energy Technology Co.,Ltd.,Jinan 250101,Shandong,China)

机构地区：[1]山东建筑大学热能工程学院 [2]山东中瑞新能源科技有限公司,山东济南250101

出　　处：《储能科学与技术》2023年第12期3635-3642,共8页Energy Storage Science and Technology

基　　金：山东省高等学校青创科技支持计划(2019KJH012);山东建筑大学博士基金(X22032Z)。

摘　　要：温室大棚利用温室效应原理,维持植物适宜的生长环境。当光照强烈时,大棚内的温度可能超过植物正常的生长温度,此时需要采取适当的降温措施。本工作将相变储热技术应用于温室大棚,采用被动控温原理降低大棚的峰值温度,减少主动降温的能耗。选择十二水磷酸氢二钠为相变材料,添加成核剂和增稠剂后制得复合相变材料以改善水合无机盐的过冷和稳定性问题,使用步冷曲线法、差示扫描量热仪、同步热分析仪等测试材料性能。将复合相变材料封装成板,装配到温室大棚中,在实际光照条件下测试相变板对大棚内部热环境的影响。结果表明,4%质量分数的九水硅酸钠可以将十二水磷酸氢二钠的过冷度由12℃降低至0.5℃;黄原胶作为增稠剂,当质量分数为5%时,材料循环稳定性良好;复合材料的相变温度和潜热分别为34.2℃和194.5 J/g,适合用于温室大棚。连续24 h的温度检测显示大棚的峰值温度相比未装配相变板的参考大棚降低3.5℃,峰值时间推迟32 min,高温总时长相比参考大棚明显缩短。因此,十二水磷酸氢二钠复合相变材料应用于温室大棚可以起到改善大棚高温环境,降低制冷能耗的作用。Greenhouses exploit the principle of greenhouse effect to maintain an optimal growth environment for plants.Under intense sunlight,the temperature inside greenhouses may exceed a suitable growth temperature;therefore,appropriate cooling measures must be implemented.In this study,phase-change energy storage technology is applied to greenhouses by exploiting passive temperature control to reduce the peak temperature of the greenhouse and thereby reduce energy consumption.Disodium hydrogen phosphate dodecahydrate(DHPD)was used as the phase change material(PCM).After the addition of nucleating agents and thickeners,a composite PCM was prepared,which exhibited a low supercooling degree and good cycle stability.Its performance was evaluated using the step-cooling curve method,differential scanning calorimetry,and a simultaneous thermal analyzer.Next,the composite PCM was packaged into panels and installed in a greenhouse,and the impact of the phasechange panels on the thermal environment inside the greenhouse under actual sunlight conditions was investigated.The results revealed that sodium metasilicate nonahydrate with a mass fraction of 4% can reduce the supercooling of DHPD from 12 ℃ to 0.5 ℃.Using xanthan gum with a mass fraction of 5% as the thickener,the composite PCM exhibited good cycle stability.The phase change temperature and latent heat of the prepared composite were 34.2 ℃ and 194.5 J/g,respectively,which were found to be suitable for greenhouses.Continuous 24 h temperature detection revealed that the peak temperature of the greenhouse was reduced by 3.5 ℃ in comparison with that of the reference greenhouse without phase change panels.The corresponding peak time was delayed by 32 min.In addition,the total duration of high temperature was significantly shortened in compared to that of the reference.Therefore,the application of the DHPD composite PCM in greenhouses can improve the high-temperature environment of the greenhouse and reduce the energy consumption of cooling.

关 键 词：温室大棚 相变材料 十二水磷酸氢二钠 降温能耗 

分 类 号：TK02[动力工程及工程热物理]