Zeng Changnv, Hu Chaoxin, Li Wanwan
School of Civil Engineering, Henan University of Technology, Zhengzhou 450001, China.
Materials (Basel). 2023 Jan 20;16(3):964. doi: 10.3390/ma16030964.
In order to meet the great demand for green grain storage and low carbon emissions, paraffin, high-density polyethylene (HDPE), and expanded graphite (EG) were used to produce shape-stabilized phase change material (SSPCM) plates, which were then used to reconstruct building walls for existing granaries. A new type of SSPCM plate was then prefabricated with different thermal conductivities and a high latent heat. This plate could be directly adhered to the existing granary walls. In order to evaluate the thermal regulation performance of these phase change granary walls, experiments and numerical methods were established, specifically for the summer condition. The thermal behavior of the SSPCM granary wall was compared with that of the common concrete granary wall to obtain the optimal parameters. It was concluded that increasing the thickness of the SSPCM layer can reduce the temperature rise of the wall. However, the maximum latent heat utilization rate and energy storage effects were obtained when the SSPCM thickness was at an intermediate level of 30 mm. The thermal conductivity of the SSPCM had a controversial effect on the thermal resistance and latent heat utilization behaviors of the SSPCM. Considering the temperature level and energy saving rate, a 30 mm thick SSPCM plate with a thermal conductivity of 0.2 W/m·K provided a superior performance. When compared to the common wall, the optimized energy-saving rate was greatly enhanced by 35.83% for the SSPCM granary wall with a thickness of 30 mm and a thermal conductivity of 0.2 W/m·K.
为满足绿色粮食储存和低碳排放的巨大需求,采用石蜡、高密度聚乙烯(HDPE)和膨胀石墨(EG)制备了形状稳定相变材料(SSPCM)板,然后将其用于对现有粮仓的建筑墙体进行改造。接着预制了一种具有不同热导率和高潜热的新型SSPCM板。这种板可直接粘贴在现有粮仓墙体上。为评估这些相变粮仓墙体的热调节性能,针对夏季工况建立了实验和数值方法。将SSPCM粮仓墙体的热行为与普通混凝土粮仓墙体的热行为进行比较,以获得最优参数。结果表明,增加SSPCM层的厚度可降低墙体温度升高。然而,当SSPCM厚度为30mm的中间水平时,可获得最大潜热利用率和储能效果。SSPCM的热导率对SSPCM的热阻和潜热利用行为有争议性影响。考虑温度水平和节能率,热导率为0.2W/m·K的30mm厚SSPCM板性能优越。与普通墙体相比,厚度为30mm、热导率为0.2W/m·K的SSPCM粮仓墙体的优化节能率大幅提高了35.83%。