Tests of prototype PCM ‘sails’ for office cooling
Tests of prototype PCM ‘sails’ for office cooling
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用于办公室冷却的 PCM“帆”原型测试
DOI：
10.1016/j.applthermaleng.2010.10.008
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发表时间：
2011
影响因子：
6.4
通讯作者：
S. Craig
中科院分区：
文献类型：
--
作者：
G. Susman;Z. Dehouche;Tanawat Cheechern;S. Craig
PCM模块，构造从石蜡/LDPE复合材料，进行了测试，在占用伦敦办公室，在夏天。设计变化测试了对黑色油漆或铝表面的热传递的影响，不同相变区的影响以及内部或外部散热的影响。监测模块的温度沿着气流速率、空气温度和地球仪温度。它们的小尺寸意味着对室温的任何影响都可以忽略不计。使用DSC测量PCM的热物理性质，结合环境测量，在FLUENT中构建模块的半经验模型，使用多孔性-孔隙度公式来模拟相变。使用温度测量值对所有模块进行了良好的验证，当达到最大液体分数时，温度测量值具有显著的发散性。该模型通过温度测量进行了验证，并用于生成平均液体分数和表面传热速率曲线，用于性能比较。相变材料的相变区较宽，导致潜热容量浪费。由于辐射交换，黑色模块传递热量和排出潜在存储容量比铝模块快得多。将热量排放到外部导致储热能力的增加和更高的吸热率。
PCM modules, constructed from a paraffin/LDPE composite, were tested in an occupied London office, in summer. Design variations tested the effect on heat transfer of a black paint or aluminium surface, the effect of different phase transition zones and the effect of discharging heat inside or outside. The modules’ temperatures were monitored along with airflow rate, air temperature and globe temperature. Their small size meant any effect on room temperature was negligible. Using DSC measurements of the PCMs’ thermophysical properties, in conjunction with the environmental measurements, a semi-empirical model of the modules was constructed in FLUENT using an enthalpy-porosity formulation to model phase change. Good validation was obtained for all modules using the temperature measurements with notable divergence when maximum liquid fraction was reached. The model was validated by the temperature measurements and used to generate mean liquid fraction and surface heat transfer rate profiles for performance comparisons. The broad phase transition zones of the PCMs results in wasted latent heat capacity. Black modules transfer heat and exhaust latent storage capacity significantly quicker than aluminium modules, due to radiant exchange. Discharging heat outside leads to an increase in thermal storage capacity and a higher rate of heat absorption.