相变蓄热墙体对日光温室热环境的改善

该文以北京市郊区某蔬菜种植基地日光温室为研究对象,将所研制的新型相变蓄热墙体材料应用于日光温室北墙内表面,通过提高温室墙体太阳能集热与蓄热能力,达到提高太阳能热利用效率和改善日光温室热环境的目的。采用40mm厚相变蓄热墙体材料板的试验温室与同尺寸的普通砖墙的对照温室比较,2010年12月21日至2011年1月18日的比较试验结果表明:草帘开启时段(白天),前者后墙表面温度平均提高1～2.7℃,耕作层(0～20cm)土壤平均温度提升0.5℃,室内环境平均温度提升0.2～2.1℃;草帘关闭时段(夜间),试验温室后墙表面温度平均提高2.1～4.3℃,耕作层土壤平均温度提升0.5～1.4℃,室内环境平均温度提升1.6～2.1℃。所研制的相变蓄热墙体材料较好地改善了温室作物生长热环境,提高了日光温室的太阳能热利用率。

Improving thermal environment in solar greenhouse with phase-change thermal storage wall

In this paper,the two solar greenhouses with the same sizes of a vegetable planting base located in Beijing were researched,and one was taken as test greenhouse,the other reference greenhouse.The phase change materials(PCMs) was applied on the inner surface of the test greenhouse’s north wall in order to enhance the wall’s ability to collect and store solar energy and increase the utilization rate of solar energy,and then improve the indoor thermal environment of the greenhouse.According to the measured data from Dec.21,2010 to Jan.18,2011,the results showed that the thermal performance of the test greenhouse with 40 mm thickness PCMs was better than that of the reference greenhouse with conventional brick materials.During the opening of the heat preservation quilt in the daytime,the inner surface average temperature of the north wall of the test greenhouse was about 1-2.7 ℃higher than that of the reference greenhouse,the soil average temperature of the plow layer and the average indoor ambient temperature of the test greenhouse were about 0.5℃ a nd 0.2-2.1 ℃ higher than that of the reference greenhouse,respectively.During the closing of the heat preservation quilt at night,the inner surface average temperature of the north wall,the soil average temperature of the plow layer and the average indoor ambient temperature of the test greenhouse were about 2.1-4.3 ℃,0.5-1.4 ℃ and 1.6-2.1 ℃ higher than that of the reference greenhouse,respectively.So the PCMs can improve the thermal environment for crop growth and increase the utilization rate of solar energy in solar greenhouse.