Study Of Determining The Inner And Outer Zones In Commercial Buildings And Air Distribut Ion Simulation

In this paper,the theoretical analysis and numerical simulation method are used to analyze the determination of the internal and external partition boundaries of the air conditioning system of commercial buildings.Taking an actual project as an example,the air conditioning system is divided,and the energy saving and economic analysis are carried out.First of all,theoretical analysis is made on the determination of internal and external partition boundaries of commercial building air conditioning system.Based on the theory of heat balance,the calculation method of the inner and outer boundaries of standard floor,top floor and first floor air conditioning system is deduced.This paper analyzes the inner and outer boundaries of the five climate zones:cold,cold,hot in summer and cold in winter,hot in summer and warm in winter,and mild.Under the same window wall area ratio,the inner and outer boundaries of the cold regions represented by Harbin are the largest in the five typical cities,and the inner and outer boundaries of the hot and warm in summer and winter represented by Guangzhou are the smallest.The area ratio of window to wall is in the range of 0.3?0.7,and the dividing line of different climate zones is from the big to the small,which is the severe cold area>the cold area>the moderate area>the hot summer and cold winter area>the hot summer and warm winter area.The boundary between the inner and outer zones does not simply increase with the increase of the window wall area ratio,but there will be inflexion points.The inflexion points appear at the window wall area ratio of 0.6 in severe cold area,at the window wall area ratio of 0.7 in cold area,hot summer and cold winter area,and at the window wall area ratio of 0.4 in hot summer and warm winter,warm summer and mild winter area.The zoning boundaries of different directions of the same floor are different.The change of the zoning boundaries of the first floor in the north,South and east-west directions is greater than that of the standard floor and the top floor.The range of the outer zone of the same direction to different floors has a certain rule,that is,the range of the outer zone is from large to small as one floor>top floor>standard floor;the range of the outer zone of the first floor in the severe cold area and the cold area changes more obviously than other areas.Then the simulation analysis of the boundary between the inner and outer zones of the air conditioning system in different climate zones is carried out and compared with the theoretical analysis.The results show that the difference between the simulation value and the theoretical value is very small.The maximum deviation is 0.13m in the south direction in the severe cold area,and the deviation rate is 3.5%.Within the allowable range,the two agree well.At last,a practical project in Shenyang City is divided into the inner and outer zones of the air conditioning system,and the zone boundaries of different floors and different directions are obtained.According to the analysis of energy conservation and economy of the actual project,the initial investment of the air conditioning system will be increased when compared with the internal and external zoning.The initial investment will be increased by 38.6 yuan or 6.7%for each 1 kW·h of refrigeration capacity obtained.In winter,the way of using fresh air to eliminate the residual heat in the internal zone can save 560400 yuan of operation cost and 8.2 kWh/m2 of energy consumption,which has better energy conservation effect.