LAUSR

Abstract Nowadays, new generations of building envelope need to manage the energy exchange between outdoor and indoor environment responsively and save the building energy. A significant amount of solar heat gain in buildings comes through the windows. The transparent envelope also must answer to visual requirements allowing for external vision but guarantying comfort conditions. In this framework, this article aims to test numerically the thermal performance of a new design of multifunctional glazed window combining the most recent technologies used in building envelopes. Five distinct window designs combing phase change material (PCM), vacuum glazing (VG), photovoltaic (PV), and air cavity were numerically tested for hot weather conditions. The proposed window designs slide inside the wall of the building. A comprehensive transient Multiphysics model coupling the thermo-electric model of the PV, melting and solidification model of the PCM, and the heat transfer mechanisms in the vacuum and air gaps are developed. The model is step by step validated with data in the literature. Various PCM types and PCM thickness are investigated. Among the five investigated window designs, the result showed that the window, including the air gap with PV, PCM cavity, and VG, is the optimal design for the indoor air's thermal isolation. Simultaneously, the PCM with a melting point of 35 ˚C and thickness of 50 mm is the best performance material in a hot arid region in summer at Cairo. The proposed multifunction window generated maximum electrical power intensity of 162 W/m2 at received solar radiation of 1000 W/m2.