Study On Operation Characteristics Of Ground Source Heat Pump System Of A Residential Quarter In Summer

As a high efficiency energy saving and renewable energy available technology, ground source heat pump technology which is important for the today situation of facing energy crisis,reducing building energy consumption and advocating enviroment protection has received much attention from departments of home and broad government and researchers,and has been found widly in applications of practical engeering. The operation of the ground source heat pump system of a residential quarter had been tested continuously for 77 days in summer,and a simulation model of the ground source heat pump system was built.Based on test data and simulation results,this thesis analysed factors of affecting performance of the ground source heat pump system,the change of soil temperature and operation charactristics of the ground source heat pump system.Firstly,the refrigeration condition of the ground source heat pump system which includes the original soil temperature test,variable condition tests and soil temperature recovery test at end of operation was tested.Based on analysis of test data,this thesis drew conclusions of operation charactristics of the ground source heat pump system in variable conditions,the system energy consumption and the recovery of soil temperature field.Secondly, according to actual building structure,the building model was built in DeST platform and the hourly cooling load of the building for 2880h was simulated by setting parameters of Qingdao meteorology,equipments power and the time of work and rest.Then,this thesis obtianed cooling load characteristics of Qingdao residential building on the basis of analysing hourly cooling load of typical day.A simulation model of the ground source heat pump system which contains building load module,heat pump units module,ground heat exchanger module,water pump module and control module was built in TRNSYS platform. Besides,modules of the ground source heat pump system model were analysed respectively,and the effect of coupling relationship among modules on the performance of the ground source heat pump system was explored.Finally,the model of he ground source heat pump system was verificated by using test data and the goodness of fit was high.Because of low occupany rate of the residential quarter which was only 54.7% and could not reflect the performance of high load rate,so conditions of occupany rate respectively at 100%,90%,80% and 70% were simulated.Then this thesis came to conclusions of change of inlet and outlet temperature of water source side,change of average soil temperature, performance of the ground source heat pump system and change of heat tansfer at unit length of ground heat exchanger.By comparing results of variablle conditions,this thesis could provide basis for design of ground source heat pump system and running control strategy.