Effect of emissivity of shading device and air flow inside cavity of Double Skin Facade for energy saving and Thermal Comfort in buildings: A CFD modeling

Abstract

Now a days, the need for increased indoor comfort together with the reduction of energy consumption in buildings are vital factors. Envelope systems and their influence on HVAC & lighting systems are playing a very important role in this. The improvement of the thermal comfort, the visual comfort and the buildings ventilation equipped with high glazing surfaces, generates significant energy savings. Solar Radiation will cause major role in increasing cooling load inside the buildings. In order to eliminate this problem Double Skin Facades and their shading devices was introduced. A double skin façade consists of a double glazing separated by a ventilated air space with two openings at the top and bottom of the façade equipped with internal shading devices. This paper aims that CFD modeling of Double Skin Facades and influence of shading devices inside the cavity. Air flow and heat transfer through the Double Skin Facade was also studied. The flow inside the cavity naturally ventilated and low turbulent flow is considered. Radiation model used in this study is Discrete Ordinate Model in FLUENT software. The variation of heat transfer with different emissivity, air flow rates is studied in energy savings point of view. The parameters which influence flow inside the cavity such as temperature, velocity, slat angles etc is analyzed and variation is noted.