相变蓄热装置降低夏季塑料大棚温度的波动

Fluctuations of phase change heat storage devices for reducing temperature in plastic greenhouses in summer

为研究相变蓄热装置的使用对塑料大棚内部温度波动的影响,文中设计制备了一种传热性能良好的膨胀石墨(EG)/石蜡复合相变材料及相变蓄热装置,并将该装置放置于塑料大棚(实验组)中进行测试。通过采集6种夏季天气条件下的该塑料大棚以及未放置相变蓄热装置的塑料大棚(对照组)内部温度随时间的变化数据,分析结果表明:在晴天天气下与对照组相比,实验组在不通风不遮阳情况下可以降低棚内温度2.4℃,减小13%的温度波动;通风不遮阳情况下可以降低棚内温度3.3℃,减小16%温度波动;通风遮阳情况下可以降低棚内温度2℃,减小棚内8%的温度波动;不通风遮阳情况下可以降低棚内温度1.9℃,减少温度波动8%。相变蓄热装置在雨天的使用效果不佳;但在阴天则可以继续发挥作用,有效降低了塑料大棚内的温度波动。

In order to study the influence of the use of phase change heat storage devices on the internal temperature fluctuations of plastic greenhouses,an expanded graphite(EG)/paraffin composited phase change material and phase change heat storage device with good heat transfer performance was designed and prepared.The device was placed in a plastic greenhouse(experimental group)for testing.By collecting data on the internal temperature changes over time in the plastic greenhouse and the plastic greenhouse without phase change heat storage device(control group)under 6 summer weather conditions,the results show that comparing with the reference greenhouse in sunny weather,the phase change greenhouse can reduce the internal temperature by 2.4℃and reduce the temperature fluctuation by 13%under the condition of no ventilation and no shading.Under the condition of ventilation and no shading,the internal temperature can be reduced by 3.3℃,reduce the temperature fluctuation by 16%.In the case of ventilation and shading,the internal temperature can be reduced by 2℃,and the temperature fluctuation can be reduced by 8%.In the case of no ventilation and shading,the internal temperature can be reduced by 1.9℃,and the temperature fluctuation can be reduced by 8%.Phase change heat storage devices were invalid in rainy days,but they can continue to work in the cloudy days of hot summer,reducing the temperature in the plastic greenhouse.