Application Research On The Ground Source Heat Pump System In Hefei

At present, the most commonly used cold source and heat source of air conditioner in our country are based on electric power and fossil energy (coal, oil, gas), especially, coal consists the most part of the energy, the energy structure is unreasonable, the energy utilization ratio is low, and the environment is seriously polluted. From the viewpoint of sustainable development, while choosing the cold source and heat source of air conditioner, we should consider from respects such as energy-efficiency, environmental protection, etc. The Ground Source Heat Pump (GSHP) air-conditioning system has been a kind of new technology to save energy and protect environment.This paper discussed mainly following several questions:First, This paper describes the theoretical basis of the heat transferring model, introduces several typical heat transferring models, according to the heat transferring characteristics of the U-tube, sets up the model of buried heat exchanger for ground-coupled heat pump system, programs the solving procedure of heat transfer content per meter pipe. Introduces the designing processes of the GSHP system and analyzes the influence on heat transfer content per meter pipe of designed outlet temperature of the circling liquid in buried heat exchangers, buried distance and drilling depth, and then provides reference for the Chosing of parameters during the designing of the ground-coupled heat pump systems.Second, Based on the designing and operating of some office-building GSHP air-conditioning system, the paper chooses four kinds of commonly used cold source and heat source systems and carries on comparative analysis with ground-coupled heat pump system. According to the architectural load, the article chooses the main equipments of every cold source and heat source system, calculates the initial cost of every project on the base of the market price of every kind of equipment, meanwhile, analyzes the influences on environment through calculation. According to the energy price of Hefei, the operating expenses of every project is obtained, and economic evaluation of every project is carried out with annual cost approach. In order to master the capacity of heat exchanger corresponding to different strata and mensurate the soil temperature field's change before and after the operating of the GSHP system around vertical buried heat exchanger, the data are measured in the course of the construction of the project. The temperature of every stratum is steady generally. So the situation doesn't appear that the buried heat exchanger due to the imbalance of absorbing and discharging heat throughout the year causes the heat cumulated. That shows the system is energy effective through calculating the system's COP.Third, Taken the hybrid GSHP with cooling tower asistance in some guesthouse as an example, the article introduces the designing of the ground coupling tube system, engages in ground heat exchange testing before construction, meanwhile, according to the winter and summer heat balance, determines burying way and quantity, describes emphatically the ground heat exchanger's calculating, on the basis of the GSHP system's balance analysis of absorbing heat and discharging heat, chooses the cooling tower, compares the GSHP system with the traditional water-cooling unit plus electric boilers system from coal consumption and draws a conclusion that the GSHP system is energy effective. The article compares the GSHP system's economy with the traditional air-conditioning systems' from main factors of economy analysis such as initial cost, operating expenses, lifecircle investment, etc. At last, This paper describes the ground-loop heat exchanger's main construction methods.The research conclusions provide references of reasonable design, construction and economic analysis of ground-coupled heat pump system, and let investors have further understanding of ground-coupled heat pump system's design, construction and economy, enable ground-coupled heat pump, the new and vital technology to obtain application and generalization as soon as possible in Hefei.