【作者】 王茂盛；

【导师】 刁乃仁；

【作者基本信息】 山东建筑大学 ， 制冷及低温工程， 2010， 硕士

【摘要】 随着节约能源与环境保护成为当今科学技术发展的重要方向,建筑领域里对降低空调采暖系统能耗的研究越来越受重视。在这种背景下,地源热泵技术由于利用大地中的大量低品位热能来实现对建筑物的供热制冷,并且高效环保,得到了越来越多的应用。地源热泵与传统空调最大的区别就在于地热换热器,合理的设计地热换热器可以节省初投资,有效的利用土地,并使运行安全可靠,降低系统的运行成本。地热换热器是地源热泵系统的重要组成部分,地热换热器循环液进出口温度的设定是否合理,对整个地源热泵系统能否满足要求和正常的使用关系重大。所以对地热换热器循环液进出口温度进行研究非常必要。首先,合理准确的建筑负荷计算是地热换热器设计计算的基础。本文将介绍建筑负荷计算的方法和应用计算机技术的建筑负荷模拟软件,并且对建筑逐时负荷进行累加处理,得到放入地热换热器中的累计负荷。其次,应用“地热之星v3.0”对济南地区某建筑进行模拟,设定不同的地热换热器循环液进出口温度,对地热换热器的设计长度进行分析讨论,并分析各种温度变化条件下,地埋管每米的平均换热量。对不同构造(单U、双U)的地热换热器换热性能进行了对比模拟。分析对比了两种不同构造(单U、双U)连续运行时的地下循环液温度变化情况。在连续运行过程中,换热器附近温度状况持续恶化,对系统运行不利。通过采取可控间隙运行的方式,让土壤温度有一定的恢复时间,提高换热率以减少换热器数量,可以节省土壤资源和建设成本。在间歇运行的模拟中,分析了对应的地热换热器循环液进出口温度的变化规律。再次,以实际地源热泵工程为例,并进行设备的选择以及初投资计算,然后将地源热泵系统的冬季和夏季运行费用累加即得全年总运行费用。并与三种空调形式进行经济分析,运用费用年值指标对几种方案进行比较。结果在循环液温度较为合适时地源热泵方案比其他空调系统更经济合理,具有明显的技术经济优势。本文所做的工作,主是设计地源热泵地热换热器循环液最佳的不同进出口温度,循环液出口温度的设定不仅影响系统的效率,同时也影响到系统的初投资,根据本文研究表明：采用浓度为7%的NaCl溶液时,济南夏季地热换热器循环液的最佳出口温度为：27℃-32℃,与此对应的冬季出口温度为：3℃-9℃。这些研究结果对地源热泵项目的设计与施工具有一定的参考价值,能够为本技术的推广提供有力支持。更多还原

【Abstract】 While the energy-saving and environmental protection becomes an important direction of science and technology development, more and more attention has been paid to reduce the energy consumption in buildings. In this background, more and more ground-source heat pump (GSHP) systems have been used because of their advantages such as making use of the low-grade energy source for building heating and air-conditioning, highly efficiency and environmental protection features. The GSHP system is quietly different from conventional HVAC system in its ground heat exchanger (GHE), which is buried underground to absorb or dissipate heat. Reasonable designing of the GHE would reduce the first cost of the project, make rational use of the field, ensure reliably operate and save operation cost of the project.The ground heat exchanger is the important constituent of the ground-source heat pump system. Reasonable inlet and outlet temperature of the circulating fluid in the ground heat exchanger is significant. So it is very necessary to research the ground heat exchanger.First, the reasonable accurate building load computation is the foundation of the GHE designing. This thesis introduces methods of the building load computation and the software that using computer technology to simulate. To get the load that put into GHE, we cumulate sum the hourly building load.Second, while the "Geothermal Stars v3.0" is applied on a building of the Jinan area to simulate the situation, different inlet and outlet temperatures of circulating fluid in the ground heat exchanger was set to analyze and discuss the designed length of the ground heat exchanger, and then analyze the average heat exchange capacity per meter in a varying temperature conditions. Compared simulation was done to the heat transfer properties of the ground heat exchanger of different styles (single-U, double-U) and backfill materials. And the varying temperature of the underground circulating fluid in the two different styles (single-U, double U) were analyzed and compared. It’s negative to the running of the system while the temperature around the heat exchanger continues to deteriorate during the continuous operation process. By the way that adoption of controlled space, which allows the soil temperature has a certain recovery time and improve the heat transfer rate in order to reduce the number of heat exchangers, and it can also save soil resources and construction costs.In the simulation of the intermittent operation, the corresponding inlet and outlet temperatures of circulating fluid in the ground heat exchanger was analyzed.Again, take the actual ground-source heat pump project for example, and make the choice of equipment as well as the calculation of the first cost, and then the total annual operating costs was derived from adding up the operating costs in winter and summer of the ground-source heat pump system. And it was analyzed in economic with the other three kinds of air-conditioned form, the annual cost indicators was used to compare these schemes. As a result, the way that the ground-source heat pump when the temperature of the circulating fluid is appropriate was more economic and reasonable than any other air-conditioning systems and it had obvious technical and economic advantages.The main work this paper done was to design an optimal different inlet and outlet temperature of the circulating fluid in ground-source heat pump,the enactment of the outlet temperature of the circulating fluid not only affected the efficiency but also the initial investment of the system. According to this article, studies have shown that:With the concentration of 7% NaCl solution the optimal outlet temperature in summer of Jinan is:27℃～32℃,and the corresponding outlet temperature in winter is:3℃～9℃.These researches had a certain reference value on the design and construction of the ground-source heat pump project and they can provide strong support for promotion of this technology.更多还原