Natural cross ventilation in buildings on Mediterranean coastal zones

• Published in: Energy and buildings Vol. 77; pp. 206 - 218
• Main Authors: Faggianelli, Ghjuvan Antone, Brun, Adrien, Wurtz, Etienne, Muselli, Marc
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 01.07.2014; Elsevier
• Subjects: Airflow control; Applied sciences; Building insulation; Building technical equipments; Buildings; Buildings. Public works; Engineering Sciences; Environmental engineering; Environmental Sciences; Exact sciences and technology; External envelopes; Mediterranean climate; Natural ventilation; Summer comfort; Thermal breezes; Thermal comfort; Ventilation. Air conditioning; Summer comfort; Airflow control; Natural ventilation; Mediterranean climate; Thermal breezes; Tracer technique; Climate; Thermal comfort; Buildings; Measurement result; Wind velocity; Summer; Indicator; Coastal zone; Air flow; Computing method
• ISSN: 0378-7788
• DOI: 10.1016/j.enbuild.2014.03.042

•Interest of thermal breezes for natural cross ventilation.•Proposition of climate indicators to assess natural ventilation potential.•Methodology applied with meteorological data from Corsica (France).•Airflow rate of a seaside building studied by tracer gas measurements.•Interest of controlling system studied with an empirical model. Natural ventilation of buildings is a common way to improve indoor air quality, thermal comfort in summer and reduce energy consumption due to air conditioning. However, efficiency of such a system is highly dependent on climatic conditions. This paper investigates the use of thermal breezes, characterized by moderate speeds and well-defined direction, to improve natural cross ventilation technique on Mediterranean coastal zones. The interest of this phenomenon is highlighted by the development of climate indicators with meteorological data from various places in Corsica (France). A statistical wind rose is used to give more information on main wind sectors and speed fluctuations. The natural ventilation potential is assessed by a radar plot which groups the main climate indicators for comfort ventilation and passive cooling. Tracer gas measurements on a seaside building in Corsica show that high air change rates are reached by cross ventilation during day (higher than 25ACH). Night ventilation gives more moderate results for passive cooling with air change rates close to 10ACH. As the comfort in building is related to the airflow, it is necessary to be able to control it. The issue of controlling openings to maintain a satisfying airflow is treated with the help of an empirical model. Due to the regularity of thermal breezes, it shows that even if the airflow varies greatly during the day, a minimal control on opening surface is sufficient to maintain the airflow rate on a comfortable range.