Theoretical analysis and performance evaluation of smart windows

Buildings account for one-third of the global final energy consumption, and space heating and cooling are responsible for around 40% of the building total energy use. Meanwhile, designing buildings with large glazing area has become an architectural trend since decades. To achieve energy conservation in buildings with large glazing area, the application of novel technologies is of high importance. In this study, a novel triple glazed fluidic window is introduced. This fluidic window contains one or multiple micro-structured glass panes, which can be used for fluid circulation. With this concept, different application cases can be realized, such as heating/cooling panel for indoor air-conditioning, heat exchanger for heat pump or switchable solar shading. This work concentrates on the feasibility investigation and the energy efficiency of the application cases. For the theoretical analysis, several simplified modeling methods for the triple glazed fluidic window are presented and validated with coupled heat transfer and fluid flow numerical simulation. With the presented models, this work shows that using magnetic particle suspended fluid as the circulating fluid inside the triple glazed fluidic window reduces building’s solar heat gain and thus the cooling loads becomes lower. Furthermore, when two glass panes are replaced with the capillary glass panes, the triple glazed window becomes a decentral heat pump. Moreover, over-bridging the inner and the outer fluidic glass pane enables passive cooling. A simulation study shows that this device can reach a high energy efficiency. For the future work on this subject, the author suggests that the possibility of integrating an energy harvesting device into the fluidic window, or using the fluidic window directly as an energy harvesting device, should be further explored.