Passive cooling effects of courtyards

H. Safarzadeh and M.N. Bahadori
School of Mechanical Engineering, Sharif University of Technology, Azadi Blvd., Tehran, Iran
Received 9 August 2003;
revised 7 October 2003;
accepted 30 April 2004.
Available online 26 August 2004.

Abstract

The passive cooling effects of a courtyard of a small building were determined numerically, employing an energy-analysis software developed for that purpose. The passive cooling features considered were the shading effects of courtyard walls and two large trees (of various shapes) planted immediately next to the south wall of the building, the presence of a pool, a lawn and flowers in the yard, and the wind shading effects of the walls and trees. It was found that these features alone cannot maintain thermal comfort during the hot summer hours in Tehran, but reduce the cooling energy requirements of the building to some extent. They have an adverse effect of increasing the heating energy requirements of the building slightly. The same savings in cooling energy needs of the building can be obtained through many features such as wall and roof insulation, double-glazed windows, Persian Blinds, and special sealing tapes to reduce infiltration. They all save on heating energy requirements as well.

Keywords: Courtyard; Passive cooling; Building energy analysis
Article Outline

1.
Introduction

2.
Description of the building

3.
Development of an energy-analysis software
3.1. Consideration of thermal- and flow-networks for the building
3.2. Development of the governing equations for the energy analysis of the building
3.3. Heat transfer through ground in courtyard and the basement
3.4. Determination of the shaded areas in the courtyard and on the south wall of the building
3.5. Determination of the heat transfer coefficients
3.6. Determination of air flow rate through the building due to wind effects
3.7. Estimation of the hourly ambient air temperature and solar radiation

4.
Solution of the governing equations to estimate the energy needs of the building

5.
The result of the energy simulation for the Green Building
5.1. Description of the energy conservation and the passive cooling features of the courtyard

6.
Conclusions

Acknowledgements

References



Building and Environment
Volume 40, Issue 1, January 2005, Pages 89-104