Parametric energy optimization of a ventilated facade with windows in Mediterranean climates

Abstract

Ventilated facades are an effective passive measure to improve the energy performance of buildings in warm and temperate climates such as the Mediterranean. However, although in the Mediterranean sociocultural context the use of windows is widespread, there is a lack of energy analysis of ventilated facades in combination with windows. This is due to the lack of accurate simulation tools to evaluate the energy performance of this combination because of its complex thermodynamics, which, among other issues, requires three-dimensional computational fluid dynamic tools. In this work, a parametric energy analysis of the design parameters of a ventilated façade with window openings has been performed using a three-dimensional numerical model developed by the authors that combines turbulent Navier–Stokes thermodynamic equations for air with a set of differential equations for the envelope temperatures. The results of the analysis showed the potential of the opaque ventilated façade (OVF) with windows when applied to the rehabilitation of energetically obsolete facades, achieving a remarkable reduction in heat flux with respect to these facades, a reduction that reaches 32% for the yearly heat flux when using the optimal configuration found.