The Comparison And Optimization Of The Central Air Conditioning System In A Shopping Mall In Xi'an Is Carried Out By Using Internal And External Zoning

In this paper,the internal and external zoning of the centralized air conditioning system in a large shopping mall in Xi'an is carried out.By comparing the results of the load calculation before and after the zoning,it is found that the design of the cold load in summer is the same,the heat load of the design will be reduced in winter,and the case can be reduced by 55%.Based on the data at room temperature at 26 C,the empirical formula and curve can be fitted by 1 m~2/p per per capita area index,and the cooling load of the system is reduced by about 462455W.Based on the per capita area index of 4 m~2/p,the empirical formula and the available temperature of the curve can be increased by 1 degrees centigrade,and the cooling load of the system is reduced by about 11960W.In winter,in spite of the overall heat load in the inner region,the internal residual heat can be eliminated through the new wind.The new wind only needs to be heated to 13 degrees centigrade,relative to the traditional air conditioning system(on the one hand,the new wind heating,on the other hand,the cold and heat canceling mode of the chiller)can be saved by 440 thousand yuan in each heating season.In this paper,DeST software is used to simulate the year by day load of the building.It is concluded that the maximum cooling load of the actual operation is 0.88times as much as the single installed capacity(3516kW),and is basically close to the simulated calculation of cold load,which shows that the simulation data is correct.In the original design,the installed capacity of the main engine is 2 times the calculated cooling load and 2.42 times the maximum load of the actual operation,so the design type selection is too large and the waste is serious.In this paper,the temperature,humidity and wind speed in the existing air conditioning room are measured.The temperature inhomogeneous coefficients of the first to four layers are calculated to be 1.075,0.538,0.404 and 1.400,respectively.According to the questionnaire survey,it was considered that the number of people with moderate environment accounted for 45.45%,and the number of people who thought the environment was cool accounted for 39.39%,and the total proportion reached87.8%.The thermal comfort of shopping malls was evaluated by using two indexes of PMV-PPD.It was concluded that the suitable temperature for shopping malls in summer is 24 C~25 C,and the relative humidity is 40%~65%.