Research On A Low Energy Building System Based On The Passive And Active Combined Thermal Environment Design Method

Reducing building energy consumption is important for china to alleviating the current situation of energy shortage.Energy efficient building design is to decrease building energy consumption,meanwhile satisfy the indoor thermal comfort requirement.Energy efficient building design always adopt passive design method firstly,then utilize active design method if indoor thermal comfort can not be satisfied in passive way.However,the thermal comfort is decided by all the different indoor thermal environment parameters,and the indoor thermal environment variation also play an important role on building energy consumption.The specific influence of the different passive building design mode on the building energy consumption hasn’t been taken into consideration in the above efficient building design mode.The thesis aimed to adopt a type of passive and active combined thermal environment design method to meet buildings’ indoor thermal requirement.The method is to involve the influence of passive building design on the indoor thermal environment,before it adopts active method,which is aimed to realize the integrated adjustment of indoor thermal environment parameters.The thesis studied the low energy building system based on the passive and active combined thermal environment design method,which is located at Wuhan city in the hotsummer and cols-winter zone Firstly,the thesis analyzed the passive and active combined design method,which discussed the design philosophy,the design route and the passive and active design technologies.Secondly,the thesis studied the passive and active combined thermal environment design strategies,which were derived from the analysis of the impacts of different indoor thermal environment parameters on the thermal comfort and the building energy consumption.The thesis proposed the technical route of the passive and active combined thermal environment design for the specific thermal zone,with the proper passive and active efficient building technologies.The low energy building system based on the passive and active combined design method involves the following aspects: efficient building envelope system adopts the thermal performance optimization design,active ventilated envelope design and the climate adaptive fenestration design.The indoor thermal conditioning system utilizes the air conditioning technology,the underfloor air distribution mode and the task-ambient air conditioning technology.The ground sink direct cooling and heating system provides the indoor with conditioning water which gains from underground.The thesis used simulational modeling method to study the operating characteristics and the system efficiency of the low energy building system,and this simuilation study was based on the system’s measurement study.The thesis adopted building energy consumption simulation method and system mechanism modeling method to model the low energy building system’s operation,which is to investigate the impacts of passive and active combined thermal environment design.,such as to investigate the variation of the indoor mean radiant temperature,indoor setpoint temperature and the building system’s efficiency.The study results reveal indoor mean radiant temperature’s influence on indoor thermal comfort is mildly weaker than indoor air temperature,but obviously stronger than indoor velocity and air relative humidity.It explains the importance of the passive and active combined thermal environment design method.The study results show ventilated envelope can improve indoor mean radiant temperature obviously both in summer and winter.The efficient building envelope system can reduce indoor mean radiant temperature 1.60 ℃ in summer,and increase the mean radiant temperature 3.44 ℃ in winter.In accordance,the improvement of indoor setpoint air temperature can achive 0.63 ℃ in summer,and 2.71 ℃in winter.The ground sink direct cooling and heating system can provide comfortable indoor thermal environment with excellent system efficiency,but fail to achive them in winer.This is caused by the limitation of the underground temperature in heating season.To solve this problem,the utilization of solar thermal system is considered to integrated in this low energy building system in future.Lastly,the study discussed the design of the low energy building system based on the passive and active combined thermal environment design method,which is to provide reference to the similar efficient building design program.