A numerical approach to evaluating what percentage of a living space is well-ventilated, for the assessment of thermal comfort

• Published in: Energy and buildings Vol. 38; no. 9; pp. 1093 - 1103
• Main Authors: Bastide, Alain, Lauret, Philippe, Garde, François, Boyer, Harry
• Format: Journal Article
• Language: English
• Published: Elsevier 2006
• Subjects: Engineering Sciences; Mechanics; Physics; Thermics; CFD; Bioclimatic; Tropical climates; Large openings; Natural ventilation
• ISSN: 0378-7788

A bioclimatic approach to designing comfortable buildings in hot and humid tropical regions requires, firstly, some preliminary, important work on the building envelope to limit the energy contributions, and secondly, an airflow optimization of the building. For the first step, tools such as nodal or zonal models have been largely implemented. For the second step, the assessment of air velocities, in three dimensions and in a large space, can only be performed through the use of detailed models such as with CFD. This paper deals with the improvement of thermal comfort by ventilating around the occupants. For this purpose, the average velocity coefficient definition is modified to be adapted to CFD and the areas involving movement or the living spaces. We propose a new approach based on the derivation of a new quantity: the well-ventilated percentage of a living space. The well-ventilated percentage of a space allows a time analysis of the aeraulic behaviour of the building in its environment. These percentages can be over a period such as one day, a season or a year. These kinds of results are helpful for an architect to configure the rooms of a house according to their uses, the environment, the architectural choices and the constraints related to the design of bioclimatic buildings.