温室储热器隔热层与蓄热工质结构设计与性能分析

Structural Design and Performance Analysis of Thermal Insulation Layer and Heat Storage Medium for Greenhouse Heat Storage

为解决因连续雾霾天气或阴雨雪天气而导致温室内温度过低,以及现有日光温室储热器散热量大、跨时蓄热量不足的问题,通过对储热水箱外隔热材料及水箱结构进行优化设计和蓄热工质组合研究,实现了温室储热装置跨时储热、分段缓释放热。实验表明,采用隔热涂料+气凝胶+橡塑保温棉的组合隔热效果较好,其24 h散热量比单一隔热材料减少散热0.367 MJ;设置水箱隔热材料厚度为80~120 mm,采用体积为6~10 m^(3)、高径比为1∶1的圆柱体蓄热水箱,既可保证较低的有效散热率,也能控制工程施工成本;采用复合相变材料组合增大了水箱蓄热量,优化了放热过程,并实现了热量分阶段缓释。建立了水箱有效蓄热量与水箱体积、相变填充体积的计算模型,利用该模型可根据不同地区热负荷和水箱储热时间配置适当的储热水箱。

Aiming to realize the span-time heat storage of the greenhouse heat storage device and release the heat slowly,the design of thermal insulation materials outside the hot water storage tank and the structure of the water tank were optimized,the relationship between the combination of phase change materials inside the water tank and heat storage and release were studied.Experiments showed that the combination of thermal insulation coating+aerogel+rubber-plastic thermal insulation cotton had a better thermal insulation effect.It reduced heat dissipation by 0.367 MJ per unit time compared with a single thermal insulation material.And it was better to set the thickness of the water tank insulation material in the range of 80~120 mm.The volume of the greenhouse heat storage device was 6~10 m^(3) and the cylindrical water tank with a height-to-diameter ratio of 1∶1 had low cost and good heat storage effect.The composite phase change material combination increased the heat storage of water tank,the heat release process was optimized and the effect of slow heat release in stages was realized.A calculation model for the actual heat storage of the water tank was established with the size of the water tank and the phase change filling volume.Applying this model,the hot water storage tank was configured according to the heat load of different regions and the heat storage time of the water tank.