| id |
cf2011_p049 |
| authors |
Hii Jun Chung, Daniel; Chye Kiang Heng, Lai Choo Malone Lee, Ji Zhang |
| year |
2011 |
| title |
Analyzing the Ventilation Performance of Tropical High Density Residential Precincts using Computational Fluid Dynamics |
| source |
Computer Aided Architectural Design Futures 2011 [Proceedings of the 14th International Conference on Computer Aided Architectural Design Futures / ISBN 9782874561429] Liege (Belgium) 4-8 July 2011, pp. 351-366. |
| summary |
Major cities in the world are getting bigger as they continue to grow to cater for more population increase. These cities normally forced the urban planning to go high density. In the tropical context, high density cities like Singapore and Hong Kong do not have the luxury of space to go low rise and compact. These cities have to build to the floor area ratio of 4 and above to cater for the population. Their only solution is to go up, as high as possible, to the extent that the natural wind flow pattern will be altered, which brings environmental impact to the people. This is generally not good since wind flow helps to maintain the thermal comfort of the people as heat and pollutants are being channeled out of the city to avoid Urban Heat Island effect. In the tropical context, wind flow is crucial to maintain people’s comfort as the temperature is generally very high from the exposure of the sun for the entire year. Studies have shown that wind flow plays the most significant part in maintaining human comfort despite exposing to direct sunlight in the tropics. Therefore, wind flow analysis is extremely crucial to make the design sustainable and energy efficient, as people will not have to depend on mechanical ventilation to compensate for the lack of wind flow. Computational Fluid Dynamics (CFD) has always been used in the field of architecture, urban design and urban planning to understand the patterns of wind flow through the built environment apart from wind tunnel tests. The availability of more powerful hardware for the mainstream computer users as well as the lowering costs of these computers made CFD more possible to be adopted in the design world today. This also means using CFD in the design process, especially to analyze the impact of the design to the current site conditions and annual wind patterns will help the new design to be more responsive to the site. The interest of this paper is to analyze the high density typologies to see how well they respond to the local wind flow pattern. A typology is considered acceptable when the wind flow going through the site is still maintaining acceptable wind speed. This means it does not block off the wind and create stagnant spaces. Different designs generate different typologies which will respond differently to the wind pattern. The study aims at comparing the local high density typologies in terms of their response to the wind. Changes to a typology can be explored too to see if the performance will be different. For a typology which is considered a total failure in terms of response to wind, it may improve its performance if the orientation is altered. The CFD software can also parametrically respond to the changes of the typologies’ dimensions. This is helpful to see how much more a typology can still be performing well before failure by increasing the floor area index. The easiest way to do this is to pump up the building height. In conclusion, designing in response to wind is extremely important as it is more sustainable and responsive to Urban Heat Island effect. A design which responds well to the wind patterns will help save cost of cooling load and fan expenditure. The people will also be more willing to use the outdoor spaces which will as a whole generate more vibrant city spaces. As a result, a high density city with huge population count can still enjoy good thermal comfort if the general urban planning and design respond well to wind. |
| keywords |
computational fluid dynamics, sustainability, high density, urban design, airflow, ventilation |
| series |
CAAD Futures |
| email |
|
| full text |
 file.pdf (13,861,534 bytes) |
| references |
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| last changed |
2012/02/11 19:21 |
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