Hygrothermal Behaviour of Continuous Air Chambers on Stone Panels Façades through CFD and IRT

Abstract

Façades of buildings with stone cladding are widely used in contemporary architecture. This research work analyses the aerodynamic, thermal and relative humidity behaviour of this type of façade. One of the main novelties of the article is the analysis of air flow and temperature of the air chamber through finite elements with computational fluid dynamics (CFD). Ten three-dimensional models were designed to study the various parameters that influence the behaviour of the façade, including the thickness of the air chamber and the velocity of the outside air. A qualitative and quantitative analysis of temperature and humidity makes it possible to determine the areas susceptible to generating condensation. Infrared thermography (IRT) is used to obtain the actual outside temperature, which is used in the validation of finite element models. The temperature is reduced by 47% with air chambers of 3 cm instead of 1 cm with soft outside air velocity, and by up to 60% with moderate air velocity. In these cases, relative humidity increases by 96% and 74%, respectively. When the results obtained in CFD vary considerably in a particular area with respect to IRT, a possible pathology is identified. This work provides better knowledge on the durability of material and façades.