Assessment of the Use of Venetian Blinds as Solar Thermal Collectors in Double Skin Facades in Mediterranean Climates

Abstract

The global trend on energy integration and building efficiency is making both researchers and building developers look for technical solutions to use facade surfaces for energy harvesting. In this work, the assessment of the thermal performance of a double-skin facade (DSF) with a venetian blind-type of structure used as a solar thermal collector by means of computational fluid dynamics (CFD) is presented. A Venetian blind collector would allow for heat rejection/energy harvesting and exterior views simultaneously and can be easily integrated into the DSF aesthetical design. For the purposes of this study, the modeled facades (south, west, and east-oriented) were set to be located in Barcelona (Spain), where large solar gains are a constant condition throughout the year, and such large semi-transparent envelopes lead to interior over-heating in buildings, even during the winter. For the studied facades, both the reductions in radiative heat gains entering the building and the heat recovery in the Venetian blind collector were evaluated for a yearlong operation.

Keywords

• double skin facades
• computational fluid dynamics
• solar thermal collector
• energy integration
• thermal performance analysis