Study On The Reconstruction Strategy Of An Existing Public Building Chilled Station In Dalian

At present,China's building construction energy consumption accounts for about 1/3 ofChina's total energy consumption.The air-conditioning energy consumption accounts for 40%to 60% of the total building energy consumption in large public buildings such as hotels,hotels,and office buildings.The author has investigated 24 public buildings and measured 11 chilled stations in Dalian.This article takes one of the buildings with the worst performance as the research object(test building),and conducts a study on the optimal operation of the chilled station.The cold and heat source of test building was Li Br absorption chillers.There was a problem of test building with the improper selection of the building cold source scheme and low energy efficiency of the equipment.So the research on the optimal operation method of the chilled station was carried out.First of all,the expert survey method was used to study the primary selection method of cold and heat source scheme,and the evaluation indexes and weights as well as the qualitative evaluation index values were determined.The weights are: initial investment 0.18,operating cost 0.18,impact on the environment 0.15,safety 0.20,technological advancement 0.21,and operational management 0.09.Significance test was done to ensure that the weight results were true and credible.The cold and heat scheme primary selection method was applied to test building and the preferred result was in line with the actual conditions of the project.Cold and heat source scheme optimization software was compiled to facilitate engineering applications.Secondly,the optimal operation strategy of the chilled station is proposed to define the device contribution rate(device contribution rate refers to the ratio of the change in the cooling capacity to the change of a certain device power when the cooling capacity changes),and it is verified that when the cooling capacity is constant and the contribution rate of each equipment of the chilled station is the same,the energy consumption of the chilled station is the smallest,and the operating energy efficiency ratio is the highest.On this basis,the optimal operation strategy of the chilled station is proposed.Thirdly,in order to test the operation effect of the chilled station optimal operation method,a TRNSYS simulation platform of the chilled station was established according to the scheme of the cold and heat source selected from the cold and heat source primaryselection method.The mathematical models of chilled station equipments were established and verified,and then the device custom TRNSYS modules were established.So the chilled station TRNSYS simulation platform was established with the building module.Finally,the test building was taken as an example to simulate and analyze the optimal operation method of the freezing station.The results are as follows.(1)After the scheme was optimized,the Design Energy Efficiency ratio of air-conditioning engineering of the test building was 3.09,which was 1.14 times that before the primary election;the average value of Seasonal Energy Efficiency Ratio of air-conditioning engineering(SEER)was 1.45,which was 1.77 times that before the reform.(2)After using the chilled station optimization operation strategy,when the cooling load was 1180 k W,1160 k W and 1140 k W,the SEER of the test buildings increased by 20.79%,24.06% and 25.03% respectively,compared with the cold and heat source scheme.