Natural ventilation and thermal performance under different opening configurations in a classroom

Abstract In school buildings located in hot tropical areas, it is a common practice to use mechanical climate control systems to avoid heat stress. The use of passive design strategies is of paramount importance for the achievement of thermal comfort with low energy consumption. Hence, buildings’ openings play an important role, as they have an impact on the amount of solar radiation received and on the internal air flow distribution pattern. The objective of this study was to evaluate the thermal performance in classrooms with different window and door model configurations in Vitória/ES and Belém/PA, Brazil. Simulations of thermal performance were conducted to analyse the intensity of thermal discomfort and energy consumption, while the aid of Computational Fluid Dynamics tools enabled the verification of details of the air velocity and temperature fields. The results show that the addition of a ventilated sill increases air velocity at the inlet opening and significantly improves thermal performance in the classroom. The use of brise-soleil reduces energy consumption in the classrooms in Belém and Vitória by up to 50% and 13%, respectively. The study helps in the selection of more efficient openings, adapted to the climatic conditions of each region.