Performance Evaluation of a Reversible Flow Double Skin Façade

Double-skin facade (DSF) is an architectural/ engineering solution developed from the need to increase comfort in buildings with full glazed facades. The actual concept of holistic approaches to the building energy system considers DSF as an element of an Advanced Integrated Facade. DSF were developed for colder climates and uncertainty remains on their applicability to warmer areas due to higher probability of overheating. Moreover there is a need for data in order to properly evaluate how they work from comfort and energy use points of view and to improve and validate models and predictions from design tools (Hoseggen et al., 2008). In order to evaluate the thermal behaviour of such a facade LNEC (39" N) assembled a south facing test facility allowing changing among some of the possible configurations. Being a reversible flow type of DSF it means that it is possible to test configurations such as (according to the classification established within the IEA ANNEX 44 (Marques da Silva and Gosselin, 2006)): Outdoor Air Curtain (OAC); Indoor Air Curtain (IAC); Exhaust Air (EA), or; Supply Air (SA). It is also possible to use any kind of ventilation type, the layout being established as a box window (BW) or, as a limit, a Buffer (Bf) configuration. Some of these DSF configurations have been tested by others authors through either test cells experiments (Saelens, 2002) or field monitoring (Corgnati et a1.,2003; Marques da Silva et al., 2005, 2006, 2008 - within IEA-ECBCS Annex 44). The main goal to achieve consists on assembling an hybrid ventilation system based on the DSF, the project's first phase being the establishment of an appropriate type and position of the shadow device. The first type tested, and reported here, is a roller blind and results show that it's position within the DSF gap, as well the flow path, has influence on air temperatures.