Modeling of an active facade containing Phase Change Materials
Résumé
Today there are several technologies to improve energy efficiency in buildings. One of the most used methods is to intervene at the thermal envelope insulation, which reduces heat losses in winter or gains in summer. A more advanced technique is to design an active envelop (coupled to the ventilation system) to make the best solar gains.
The Trombe wall is a well-known technology to exploit solar radiation storing thermal energy in the building envelope and restitute it during night for the winter application. This system can so reduce the energy requirements of the building ensuring a level of comfort to the occupants. For the thermal energy storing of this structure it is possible to introduce phase change materials (PCM), which allows an increase of the the wall’s performance, by reducing the thickness, which is also a benefit to the architectural level.
This paper presents a numerical code for simulating the behavior of a Trombe wall incorporating one or two layers of PCM. For this, we started with an existing model under TRNSYS environment (Type36) representing a classical Trombe wall and we changed it to allow the introduction of phase change materials. Parametric studies are then presented and analyzed.
The results show that, compared to conventional Trombe wall, phase change materials present several assets and ensure a reduction in heat loss increasing the thermal performance of the façade.