【作者】 刘正华；

【导师】 陈汝东； 李芃；

【作者基本信息】 同济大学 ， 制冷及低温工程， 2007， 硕士

【摘要】 地源热泵系统，是一种节能和环保的热泵技术。使用地源热泵可以减少矿物燃料的消耗，有利于国家改善能源结构，降低有害气体排放从而达到环保和可持续发展的目标。推广和应用地源热泵的关键技术之一是完善地下埋管换热器的传热模型。本文在综述几种传热模型理论的基础上，对单个U型埋管换热器传热过程进行研究，对钻井孔外和钻井孔内分别提出一维(径向)线源瞬态传热模型和三维准稳态传热模型。并利用有限元方法，建立轴向和径向的二维模型对埋地换热器在土壤中传热过程进行计算，得到埋管换热器传热量及附近土壤温度场的变化情况，并分析了不同埋管深度、U型埋管进液温度和流量、土壤热物性和U型埋管两支管中心间距等因素对U型埋管换热器传热量的影响。模拟计算得到大量关于地源热泵U型埋管换热器传热量和附近土壤温度场特性的数据，通过对这些数据的分析以期对地源热泵工程设计有一定的指导作用。 本文根据某实际工程对地源热泵系统与几种常规集中式空调系统进行了经济性评价，采用价值工程分析法，选取经济成本、技术使用特性和社会效益等重要方面作为功能评价对象，对各系统的功能系数和成本系数进行计算，最后得到各自的价值系数，以此来综合评价各空调系统方案的经济性。结果表明地源热泵系统虽然在费用成本方面是在所有方案中是最高的，但其具有很大技术优势和社会效益，在综合评价中其功能系数仅次于目前应用最广泛的螺杆式冷水机组+城市热网方案。因此说地源热泵是一种很有发展潜力的空调系统。更多还原

【Abstract】 Ground-source heat pump (GSHP) system has been identified as a most environment-friendly and efficient heat pump system. The more use of GSHP will reduce the wastage of mineral fuel,which will help our country adjust the energy structure and reduce the amount of exhaust gas released to protect the natural environment and achieve the goal of sustainable development. To perfect heat-transfer model for ground heat exchanger is one of key problems about GSHP popularization and application. Based on the summarization of current research situation of ground heat exchanger model theory oversea and home, this paper mainly research thermal behavior of a single vertical U-tube heat exchanger in the ground. And for the theoretical model, a transient one-dimensional line source model outside borehole and a three-dimension heat transfer model inside borehole are presented. Calculates and analyses the U-tube heat exchanger heat flux and the temperature field of the soil around borehole and. Analyses the influencing effect to heat flux and the temperature field of the soil by different factors, such as the depth of U-tubes, the inlet temperature, flow of mass, properties of soil and distance between two tubes of the U-tubes. By numerical computing, obtain a lot of data of heat flux of the U-tubes and temperature field of the soil. By detailedly analyzing the data, hope to guide the GSHP practice.Based on a actual project, Value Analysis method is selected to evaluate economy character compared GSHP system with routine air-conditioning systems. Choose the important factors such as expense, system performance, social benefit to be appraising targets. By the Value Analysis method, function-coefficient and cost-coefficient are calculated. Then value-coefficient is calculated. Uses value-coefficient to evaluate econmy character of all systems. It shows that the expense of GSHP system is highest, but its performance and social benefit is best. So GSHP system will be a more popular air-conditioning system.更多还原