본Recently, with an advancement of quality of people''s life and residential environment, concerns about urban heat island which is on the rise have been forming among the people. The urban heat island phenomenon occurred with the rapid urbanization and industrialization since the mid-20th century. The rapid growth of cities caused the lack of green area, thus artificial heat and air pollutant made urban air hotter than surrounding area. Therefore the purpose of this paper is to mitigate the urban heat island phenomenon by reducing the temperature of roof surface in summer through the scaled model experiment of PCM and Cool Roof system.
The results of this study are as follows:
1. In case of exterior finishing tile over packed PCM, the temperature of green urethane, Cool paint, and PCM was about 55℃, 45℃, and 31℃ respectively. That is, the surface temperature of PCM roof was about 24℃ lower than green urethane and about 14℃ lower than Cool paint.
In the case of wood pannel over packed PCM, the temperature of green urethane, Cool paint, and PCM was about 70℃, 50℃, and 37℃ respectively. That is, the surface temperature of PCM roof was about 33℃ lower than green urethane and about 13℃ lower than Cool paint.
2.The solar radiation of winter season was shown in this order: gray waterproofing >　green waterproofing >　PCM > Cool Roof. Otherwise, the value of albedo levels was shown as: Cool Roof > PCM > gray waterproofing > green waterproofing. Analysis showed that the value of albedo levels varied by the color of roof surface. Also this study found thermal lag of PCM which was not exposure to outdoor air, moreover, it is expected that using PCM in the roof could save heating energy.
3.In the case of aluminum pannel over packed PCM, the temperature of green urethane, Cool paint, and PCM was about 62℃, 47℃, and 34℃ respectively. That is, the surface temperature of PCM roof was about 28℃ lower than green urethane and about 13℃ lower than Cool paint.
As a result, the temperature of PCM and Cool roof surface was much low than the other finishing materials in summer. Besides, PCM and Cool roof system could not only save the heating energy in winter, but mitigate the urban heat island phenomenon.