IMPACTO DE DISPOSITIVOS DE SOMBREAMENTO NA DISTRIBUIÇÃO DE PRESSÃO EM UM MODELO GENÉRICO

Abstract

Natural ventilation in buildings is an important passive strategy to maintain indoor air quality and comfortable thermal environments. The pressure differential on buildings’ façades, quantified by the wind pressure coefficients (WPCs), directly impacts in the performance of natural ventilation. Several factors as wind direction, surroundings, terrain type, building geometry and facades’ details influence in wind pressure distribution. Many investigations use wind tunnel tests or computational fluid dynamics simulations to evaluate the Cps in regular geometries. However, few wind pressure data is available with additional architectural elements, as for example, external shading devices. This paper aims to evaluate the impact of external shading devices on the WPCs of an generic isolated with 3.0 m x 3.0 m x 2.7 m with two openings (with 1,0 m2 each), centralized and placed in opposite façades with a windowsill of 1.1 m. Thus, from its reduced version (scale 1:7,5), five configurations (without shadings, sealed model and with openings and, typologies with shading devices horizontal, combined and vertical) are tested in a wind tunnel for eight wind attack angles (0° to 90° and 180°). Results are shown using contour charts to map the wind pressure distribution on windward and leeward façades to measure the wind pressure differences between the models without and with shadings. Greater differences are observed in cases with vertical shading devices expose an oblique wind attack angle like 45°, 60° and 75°.