Experimental evaluation of an integrated phase change material blind system for double skin façade buildings

Double skin facades (DSFs) have been widely recognised as sustainable design elements for reducing energy consumption in buildings. However overheating problems in DSFs in warm seasons and locations have been reported in various studies for contributing additional increase in cooling loads in buildings. Although strategies such as utilisation of shading devices and incorporation of thermal mass into DSFs have been investigated by some researchers, there are still some technical and scientific barriers to be overcome to ensure effective heat transfer processes in the systems. This paper focuses on the experimental evaluation of an integrated phase change material (PCM) blind system based on previous theoretical study. Detailed procedures for developing the integrated blind system based on laminated composite PCM have been established which cover series of screening tests on alternative materials. Temperature and airflow velocity data were monitored and collected from a typical DSF test facility equipped with a PCM blind prototype in the summer of 2014. The data analysis showed that the integrated PCM blind system was able to stabilise the cavity temperature to about 36°C during the hottest period which showed no significant increase as compared with the ambient temperature. Even though the developed system has demonstrated some level of capacity to mitigate the overheating phenomenon in DSF, there is the need for longer term investigations into the energy storage efficiency of the PCM due to repeated charging and discharging cycling.