Application And Optimization Analysis Of Ground-source Heat Pump Combined Full Year Solar Collector Heat Storage System

With the continuous development of China's urbanization,the gap of central heating area gradually expanded in the northern urban heating areas.At the same time,a large number of isolated buildings and the majority of rural areas need environmentally-friendly and efficient way of heating in urgent,and use these fine heating methods to replace conventional coal-fired heating system or the heating system using electric direct.Although ground source heat pump(GSHP)is one of the few fine ways of heat supply in our country,there is a problem of heat imbalance in rock and soil mass in the area of annual accumulated heat load is much larger than annual accumulated cooling load.The reasonable application of the solar assisted ground-source heat pump with full year heat storage system can solve the problem of the heat imbalance in rock and soil mass well.But the research of this system is not comprehensive,and cannot support the popularization and application of the system at present.In this paper,the existing system research as a starting point,the part which has a great influence on the system and needs further research is the focus of this paper.Then the orthogonal simulation experiment was carried out,and the public building demonstration project in Xilu Town,Daxing District,Beijing,was taken as the prototype.The influence of five parameters on the stable average temperature field of the rock and soil mass was calculated,which includes installed capacity of solar collector,the initial temperature of rock and soil mass,comprehensive thermal conductivity of rock and soil mass,specific heat capacity of rock and soil mass and the spacing of underground heat exchanger.The results show that the influence of the initial temperature of rock and soil mass and installed capacity of solar collector is highly significant and the influence trend is similar on the stable average temperature field of the rock and soil mass.The influence curves of these two factors have an inflection point.After the inflection point,the significant degree of these two factors decreases gradually on the stable average temperature field of the rock and soil mass.The influence of comprehensive thermal conductivity and specific heat capacity of rock and soil mass is highly significant on the experimental result,and there is complementarity between the two factors in the common range.There is no significant influence on the experimental result for the spacing of underground heat exchanger.In order to verify the superiority of the system and prove the reliability of the simulation,this paper makes an experimental study on the solar assisted ground-source heat pump with full year heat storage system.The experimental results are in agreement with the corresponding simulation part and the energy saving of the system is verified.The influence can be controlled for heat storage on cooling system in summer and the efficiency and comfort of the system are verified in heating season.The system is economical compared to conventional ground source heat pump.Finally,according to the characteristics of the system,this paper constructs a practical evaluation system to solve the problem of the applicability of the popularization and application of the system,which evaluation system contains six necessary evaluation items.And the specific suitability index is obtained.These results provide convenience for the promotion of the system.