Effect of Porous Multi-Layer Envelope System on Effective Wind Pressure of Building Ventilation
Building ventilation performance is an important indicator of indoor comfort. However, in addition to the geometry of the building or the proportion of the opening, the ventilation performance is also very much related to the actual wind pressure of the building. There are more and more contemporary building designs built with multi-layer exterior envelope. Due to ventilation and view observatory requirement, the porous outer layer of the building is commonly adopted and has a significant wind damping effect, causing the phenomenon of actual wind pressure loss. However, the relationship between the wind damping effect and the actual wind pressure is not linear. This effect can make the indoor ventilation of the building rationalized to reasonable range under the condition of high wind pressure, and also maintain a good amount of ventilation performance under the condition of low wind pressure. In this study, wind tunnel experiments were carried out to simulate the different wind pressures flow through the porous outer layer, and observe the actual wind pressure strength engage with the window layer to find the decreasing relationship between the damping effect of the porous shell and the wind pressure. Experiment specimen scale was designed to be 1:50 for testing real-world building conditions; the study found that the porous enclosure has protective shielding without affecting low-pressure ventilation. Current study observed the porous skin may damp more wind energy to ease the wind pressure under high-speed wind. Differential wind speed may drop the pressure into similar pressure level by using porous skin. The actual mechanism and value of this phenomenon will need further study in the future.Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 373
 American Architectural Manufacturers Association. (2005). AAMA 501.1. Standard test method for water penetration of exterior windows, curtain walls and doors using dynamic pressure. Schaumburg, IL: American Architectural Manufacturers Association (AAMA).
 American Society for Testing and Materials. (2009a). ASTM E331-00. Standard test method for water penetration of exterior windows, skylights, doors, and curtain walls by uniform static air pressure difference. West Conshohocken, PA: American Society for Testing and Materials (ASTM).
 American Society for Testing and Materials. (2009b). ASTM E547-00. Standard test method for water penetration of exterior windows, skylights, doors, and curtain walls by cyclic static air pressure difference. West Conshohocken, PA: American Society for Testing and Materials (ASTM).
 Australian and New Zealand Standards Institution. (2008). AS/NZS 4284. Testing of building façades. Sydney: Australian and New Zealand Standards Institution (AS/NZS).
 Mayo, A. P. (1998). To develop a European standard dynamic watertightness test for curtain walling. Task 5. Develop the methodology for the standard dynamic watertightness test. Watford: Building Research Establishment (BRE).
 Pérez, J. M., Domínguez, J., Cano, E., del Coz, J. J., & Suárez, F. J. (2014). A comparison of methods for determining watertightness test parameters of building façades. Building and Environment, 78, 145–154. doi:10.1016/j.buildenv.2014.04.027
 Takao Sawachi, Narita Ken-ichi, Nobuyoshi Kiyota, Hironao Seto, Shigeki Nishizawa & Yuumi Ishikawa, Wind Pressure and Air Flow in a Full-Scale Building Model under Cross Ventilation, International Journal of Ventilation, Volume 2, 2004 – Issue 4, Pages 343-357 doi: 10.1080/14733315.2004.11683677
 King Fahad National Library, Image source: http://www.ada.gov.sa/ADA_e/DocumentShow_e/?url=/res/ADA/En/Projects/KFNL/index.html