Numerical Study of the Influence of Opaque External Trees with Pyramidal Shape on the Thermal Behaviour of a School Building in Summer Conditions

Abstract

This paper describes a numerical study of the influence of opaque external trees with pyramidal shape on the thermal behaviour of a school building in Summer conditions. The software used simulates the thermal response of buildings with complex topology under transient conditions. This software has previously been validated by real studies both in Summer and Winter conditions. The school building considered is localised in the South of Portugal. It has three levels divided into 97 rooms or spaces, 1277 main structures and 211 windows with plain transparent glass. In the model, the building is shaded by 49 ‘‘opaque’’ trees of pyramidal shape growing in front of the windows on one side of each building considered. The simulation considered a typical Summer school day with clear sky and with 800 occupants in the building. Two situations with the same configuration were analysed. In the first one, the trees (located in front of the windows) were placed to the West and South-West of the buildings, while in the second one, after a 180° building rotation, they were to the East and North-East. Both situations were studied with and without the presence of trees. Temperatures in the building and the occupant’s thermal comfort conditions were calculated.

Keywords

Numerical simulation Thermal behaviour Thermal comfort Trees as shading devices

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