Thermal Performance Analysis And Optimization Of Double Skin Facade Under Natural Ventilation

Because the beautiful appearance of double skin facade(DSF),more and more architects like to use it into their architectural designs.However,because of the lack of necessary theoretical guidance design,the DSF is not energy efficient.In order to provide theoretical support for the optimization of the structure of DSF,considering multiple factors such as the solar radiation,outdoor air temperature,indoor air temperature and the sky temperature,the thermal model of DSF is established.Firstly,based on the principle of heat transfer,the thermal model of DSF is introduced.The thermal model of DSF is composed of optical model,heat transfer model and ventilation model.In order to get the accurate DSF hourly solar radiation absorption and permeability,based on ray tracing method,the DSF optical model is set up.The heat transfer model of DSF is based on energy conservation,considering the factors of heat convection and absorption of solar radiation,long wave heat radiation,sky radiation and air flow effects on the DSF thermal performance.The natural ventilation model of DSF is composed of several models,such as DSF cavity air flow model,cavity pressure distribution model,transverse longitudinal flow model and DSF natural ventilation model.Secondly,the experimental platform is built.The accuracy of the model is discussed by comparing the simulation results with the experimental results of DSF thermal model.On this basis,in order to explore the application value of the thermal model of DSF,the annual energy consumption simulation time is estimated.Then,considering the influence of the change of the angle of the blind on the indoor heat and natural lighting,according to the linear weighted sum method,the optimization model of the DSF blind angle is set up.Finally,considering the influence of several factors on the thermal performance of DSF,such as the relative position of the insulating glass,the position of the blind,the height of the curtain wall,the width of the curtain wall and the height of the vent,according to the principle of orthogonal experiment,the optimization model of DSF structure is established.Research shows that the DSF model can quickly and accurately simulate the thermal performance of DSF under the condition of natural ventilation.The optimization model of the DSF blind angle can effectively guide the DSF operation control.And the model of DSF structure optimization has an important guiding significance for the design of DSF.In a word,the DSF thermal model has a significant theoretical support for the practical application of DSF.