Study On Hot-humid Environment And Operating Characteristics Of Air-conditioning In An Office Building

A good indoor hot-humid environment can not only make workers pleasure,but also improve the efficiency of staffs.It is increasingly important to create a comfortable indoor hot-humid environment.However,with the improvement of people’s living standards,the energy consumption of air-conditioning systems in office buildings is increasing.In the case of satisfying thermal comfort,it is necessary to study the personnel air-conditioning behavior by studying the operating characteristics of the air conditioning terminal of central air-con system to propose an energy-saving strategy for central air-con system.A typical office building in Changsha was taken as the research object in hot summer and cold winter area.Indoor and outdoor environmental parameters and the energy consumption of air-conditioner ends and air-conditioning unit were conducted for one year.First,according to one-year test characteristics.And the indoor hot-humid environment and comfort in different seasons were studied.The following conclusions were drawn: In the case that the terminal equipment of central air-con system was controlled by the user according to indoor hot-humid environment,the average indoor temperatures in summer,winter,autumn,and spring were respectively26.6,23.0,20.1,and 21.5 ℃.And the personnel thermal preference temperatures were respectively concentrated at 24 to 28 ℃,18 to 24 ℃,22 to 24 ℃,and 20 to 22 ℃.Besides,the average indoor relative humidity was respectively 72.2%,62.5%,43.6%,and 67.3%,which were respectively concentrated in 70% to 75%,35% to 50%,61%to 65%,and 66% to 70%.The thermal comfort level basically reached the level Ⅱ.The indoor PMV were mostly between-0.5 and +0.5(recommended value),that was to say the indoor hot-humid environment was good.It can provided reference for air-conditioner design for other office buildings in hot summer and cold winter area.Secondly,the air-conditioner terminal operating time and indoor temperature values in one year was analyzed,and logistic regression was used to develop a statistical model to predict the AC-use behaviors.Air-conditioning operating time was concentrated in working time(8:00 to 17:00);The temperatures when indoor hot-humid environment were in steady in summer and winter were recorded as the air-conditioning setting temperature,which were 25.7 ℃ and 20.0 ℃,and it provided reference for the design of air-conditioning system;The probability of turning on air conditioners was significantly related to outdoor temperatures(sig = 0.000).When the outdoor temperature was not less than 30.1 ℃ or not higher than 10.7 ℃,the probability of turning on air conditioners was not less than 80%.30.1 ℃ and 10.7 ℃were respectively defined as the cooling and heating outdoor endurance temperatures.Finally,the air-conditioning energy consumption was analyzed,and Energy Plus software was used to simulate the energy consumption of the office building.Besides an energy-saving plan for office building was proposed,in order to reduce the energy consumption of the air conditioning system.The air-conditioning energy consumption increased as the temperature difference between indoor and outdoor increasing;Reduce the indoor temperature set-point in winter,increase the indoor temperature set-point in summer,increase the shading ratio when using inner shading,increase the air-tightness of the external structures such as doors and windows,reduce building ventilation,all behaviors can reduce the air-conditioning energy consumption in office buildings and achieve energy savings.