Simulation Analysis Of Atrium Test And Renovation Of A Building In Shenyang

With the development of social economy,people's awareness of energy conservation is higher and higher.According to the research results of China Building Energy Model(CBEM)established by Tsinghua University building energy conservation research center,the total energy consumption of buildings accounted for about 19.1%of the total energy consumption in 2012,of which heating energy consumption accounted for about 30%?40%of the total energy consumption of buildings.China's annual target of new buildings has been more than 1 billion m2,designers are also constantly designed to meet the human comfort of public buildings(gyms,shopping malls,hotels,libraries,etc.).Therefore,the atrium type public building has become the main choice of most architects,its remarkable characteristics are:using large plastic steel skeleton hollow glass ceiling and glass curtain wall form of external wall,on the one hand,the atrium corridor type floor gives a person with a large space of comfortable feeling,on the other hand,most of the sunlight through the glass ceiling into the atrium,so that the atrium lighting effect is very good,thus reducing the number of people.However,the limitations of atrium buildings can not be ignored,such as:in winter,due to poor thermal insulation performance of glass roof lighting,even if there is sunshine,also makes the top temperature is verylow,increasing the heat load.During the transition season,stronger solar radiation on the roof,making the top layer temperature is very high,according to research,located in the top of the spray device in this season is easy to exceed the withstand temperature and burst.Therefore,it is very important to study the airflow organization flow rule of atrium building and take corresponding measures to reduce the problem of low indoor temperature in winter and high average top temperature in transition season.Taking a university library in Shenyang area as an example,this paper selects two working conditions of winter and transition season,and studies the distribution of air flow organization under the condition of using traditional air conditioning + solar wall coupled heating and natural ventilation system(considering only thermal pressure,unstable wind pressure,temporarily ignored).The simulation results are compared with the test results,and the CFD software can accurately predict and describe the flow field information of the simulation of the air flow organization and natural ventilation in the atrium solar wall of public buildings,so as to help improve and optimize the heating and ventilation design,and hopefully provide a reference for the future researchers to reasonably select the heating mode and ventilation mode of the atrium building.In winter conditions,through in-depth study on the atrium airflow organization by field test and CFD technology,it is found that the air velocity distribution of atrium is relatively uniform and the average air velocity is low,which meets the requirements of the public building energy-saving design standard(GB-50189-2015)in winter indoor air velocity can not be greater than 0.2m/s,and satisfies the comfort of personnel.In terms of temperature field,the temperature of the first floor is at least about 13?,the temperature of the sixth floor is at most about 25?,according to the "public building energy efficiency design standard"(GB-50189-2015),the library hall in winter heating design temperature should reach 18?,four,five,six layers of temperature are higher than 18?,and one,two,three layers of all day can not meet the standard design temperature.Using solar panel as energy-saving transformation measures to transform the library heating mode under the winter working condition,through CFD simulation of the wall cavity gas flow situation,it is concluded that using solar panel fresh air system + traditional air conditioning heating coupling effect after the average temperature of each layer of the atrium increased by about 4?,so that the temperature of each layer of the atrium can reach more than 18? and can guarantee the supply of indoor fresh air.The results of field test and CFD simulation show that the temperature of the first layer is the lowest,the temperature of the sixth layer is the highest,and the vertical temperature difference can reach about 22 ? at noon,which leads to obvious thermal stratification phenomenon.The wind speed distribution of each layer of atrium is about 0.2m/s,which satisfies human comfort.Since there is no traditional air conditioning refrigeration in the transition period,only natural ventilation mode under the action of hot pressure is used to transform the atrium airflow organization,and a typical scheme which is helpful to improve the temperature field,wind speed field and uniformity of the atrium is selected as an exampleThrough the establishment of solar wall fresh air system and natural ventilation system energy efficiency evaluation index found that both energy-saving optimization design scheme reached the energy efficiency,in the study of public buildings in the court energy-saving transformation has important significance,hoping to provide reference value for the subsequent researchers to study related topics.