Study On Load Variation Law Of Household Air Conditioning System In Hot Summer And Cold Winter Area

With the improvement of living standard and quality of life of our country,people’s requirements for indoor environment are also higher and higher.In China,the hot summer-cold winter region is hot in summer and cold in winter.Air conditioning system is needed to adjust the indoor living environment,which leads to the increasing use of household air conditioning year by year.The characteristics of household air conditioning system are intermittent and local,but the existing heating and air conditioning design manual involves less intermittent operation coefficient and simultaneous use coefficient.In addition,the recommended value is controversial in practical use.In addition,with the development of smart home,more and more people hope to further master the indoor temperature and humidity environment.The combination of air conditioning and Internet also enables people to require the indoor environment to reach the set temperature before they get home.Therefore,this paper studies the air-conditioning load variation law of residential buildings in hot summercold winter areas,especially the load variation law in the start-up stage,and the load of cold and heat sources of household air-conditioning,hoping to provide a basis for the calculation of air-conditioning load of residential buildings in intermittent operation.This paper first determines the concept of precooling(preheating)time by analyzing the thermal process of buildings,then compares the characteristics of different building load simulation software,and selects TRNSYS as the simulation software of this project.Then,the climate characteristics of hot summer and cold winter area are analyzed,and Hangzhou and Chongqing are selected as the research objects in this paper.At the same time,the paper also establishes the model of indoor thermal disturbance(human body,lighting,equipment)of the standard core family structure through literature research.Then,the air conditioning load of Hangzhou residential buildings is simulated.The initial room temperature and the time point of maximum load of each room under different natural conditions of the building are calculated by TRNSYS software.The load of each room under different precooling(preheating)time is simulated and analyzed.It is found that with the increase of precooling(preheating)time,the precooling(preheating)load required by the room decreases exponentially,and the load of intermittent operation mode is calculated.The ratio to the continuous load,i.e.intermittent operation coefficient.In addition,the change law of cooling and heating load of residential buildings with household air conditioning is simulated and analyzed,and the ratio of residential building load and cumulative load under different precooling(preheating)time is obtained.It is found that the load of household air conditioning is 50%-80% of cumulative load,that is,the simultaneous utilization coefficient is 50%-80%.In addition,the change law of room load and household air conditioning load in different precooling(preheating)time after adding fresh air is calculated,and the intermittent operation coefficient and simultaneous use coefficient are given.Finally,a simulation analysis of residential buildings in Chongqing area is carried out,and intermittent operation coefficients and simultaneous use coefficients under various conditions in Chongqing area are obtained.It is found that the intermittent operation coefficient in summer in Chongqing is slightly higher than that in Hangzhou area,and the intermittent operation coefficient in winter is slightly lower than that in Hangzhou area.There is little difference in the simultaneous use coefficient of the two areas.The intermittent operation coefficient of household air conditioners in Hangzhou area is slightly higher than that in Chongqing area.The conclusion of this paper will provide a possible scheme for the design and selection of air conditioning in residential buildings in hot summer and cold winter areas,and provide some reference value for the control strategy of air conditioning in intelligent home.