Analysis On Unsteady Thermal Characteristics Of Double Skin Fa?ade Based On The Cooperation Of Multi-factor Effect

As a developmental building envelope in recent years,Double Skin Fa?ade(DSF)has impressed greatly to people.The transparency can satisfy people’s pursuit for aesthetic appearance and meet the needs of indoor daylighting.The most important thing is that it has a great potential to improve the thermal performance,it can effectively reduce cooling and heating energy consumption by reasonably settle the open or close position of air vent,especially in hot summer and cold winter region of China.It is a complicated process of heat transfer in DSF,you need an overall understanding to thermal performance of thermal chamber if you want to design a DSF which is adapt to the local climate.Firstly,we had a further study to the heat trasfer process of DSF with a theoretical method,a dynamic heat trasfer model is established and we listed every heat balance equation of different interface.Meanwhile,the reason for natural ventilation is also been introduced,it is point out that the chamber height is the most important factors for natural ventilation.Then,we conducted a simulation reasearch for external circulating DSF with the help of CFD and WINDOW software,the solar radiation intensity,solar altitude and solar azimuth are provided by solar load model.The result show that the dynamic insulation efficiency of thermal chamber could almost over 90% in the high-intensity radiation summer daytime,it proves the DSF can effectively reduce indoor thermal disturbance caused by the high temperature in chamber.Using numerical simulation to optimize the DSF structure parameter which includes louver position,louver angle and chamber width.Results show that the chamber width has the most obvious effect to DSF heat transfer performance.Finally,we conducted an experiment on February 29,2016 and compared the simulation consequence with test data,it indicate that the mathmatical model we have established could reliably predict the distribution trend of temperature in DSF.But there are some errors between simulation consequence and test data.We summarized a few reasons by analyzing data.The principle and perfomance of DSF have been analyzed in this article,and we have do reasearch into unsteady thermal characteristic of DSF combining with simulation and experiment.This article is a good referance for performance analysis and optimization design of DSF in hot summer and cold winter region.