A Study on the Cooling Effect of Solar Screen on Varied Building Skin Materials

• Main Authors: Shu-hui Huang, 黃淑惠
• Other Authors: An-Ping Liu
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/47342715090916121770

碩士 === 國立高雄大學 === 都市發展與建築研究所 === 100 === The effect of direct sunlight on building skin during the hot summer will raise the interior air temperature due to the thermal transfer taken place in the openings and walls on building envelopes. Such kind of thermal behavior cannot provide a comfortable indoor environment for occupants in the hot season and will also lead to extremely high energy consumption and electricity cost of the air conditioners. Therefore, how to lower the temperature of the building envelope have become the basic design strategies for low-carbon buildings. The application of solar screens is one of the commonly-used examples. This study had analyzed the cooling effects of varied solar screen on different material surfaces such as steel, clear glass, reflective glass, mosaic tiles, and cement mortar. The key research findings are as follows: 1. The rankings of solar transmittance of the six solar screens are: 80% black net > 70% black net > 80% silvery net > 80% green net > 60% black net > 50% black net. 2. If solar screens directly cover the building material surfaces, the surface temperature will raise largely in principle when compared with that without covering. • The surface temperature of clear glass increases about 10oC at a maximum. • Owing to the high emissivity and thermal conduction of the steel surface, its temperature change is unapparent during the noon, which is generally decreased by 1.5oC, but the temperature will increase about 2~5oC in other periods of the day. 3. If the solar screens are 20cm above the glass, when compared with the one without solar screens, the temperature changes of two types of glass surfaces are as follows: • The surface temperature of clear glass is turned down by 11oC. • The surface temperature of reflective glasses increases 6oC during 7:00~9:00 am but decrease 2~6oC during 10:00 am~16:00 pm. 4. If the solar screens are 30cm above the material surfaces, the noteworthy cooling effects are emerged on all material surfaces in principle when compared with the uncovered one. • The surface temperature of clear glass reduces 2oC. • There are 15oC falls on the surface temperature of steel. • The surface temperature of cement mortar wall also decreases, by 11oC on the south wall and by 10oC on the west wall. • The surface temperature of mosaic tiles decreases, by 2oC on the wall southward and by 6oC on the wall westward. 5. Although the solar screens can make the surface temperatures of building materials lower than the uncovered material surfaces, they are still 5~28oC higher than the surrounding air temperatures at that time. In the night, the surface temperatures of building materials are lower than the neighboring air temperatures except the vertical walls, with a maximum value of 3oC.