【作者】 毛佳妮；

【导师】 徐玉党；

【作者基本信息】 华中科技大学 ， 供热、供燃气、通风及空调工程， 2007， 硕士

【摘要】 能源和环境问题是当今世界各国面临的重大问题,特别是随着北京申办2008年奥运会的成功,清洁能源地利用问题更成为我们面临的重要课题。地源热泵作为一项高效节能、绿色环保型的空调技术,在国外已成为一种广泛采用的供热空调方式,而在国内正处于研究和应用推广阶段,有着巨大的发展潜力。垂直深埋U型管式地源热泵以其占地面积少、可用范围广、灵活性较高、恒温效果好、换热效率高、维护费用低等众多优势,日益流行。文中首先研究了土壤温度分布特性,并针对广州地区地下60米以内土壤温度分布进行了模拟计算,分析了土壤温度的变化规律。然后建立了垂直U型埋管式土壤源热泵地下换热埋管周围土壤温度场的三维稳态传热模型,模拟了冬季工况下埋管出口水温及周围土壤温度场的分布情况。再由数值模拟和工程实地测试的方法,进一步确定不同水流量、不同岩土导热系数对地下换热器出水温度的影响程度,分析不同的回填材料、运行方式及不同的埋管间距对地下换热器传热性能的影响,为土壤源热泵系统长期高效运行提供了理论参考。此外,本文还通过对土壤源热泵系统的动态冷热负荷的变化,对地埋管设计尺寸的影响进行了进一步的计算和分析。课题选用DeST软件对广州某实际工程进行了全年动态负荷计算,在全年逐月总冷热负荷及逐月冷热负荷峰值计算结果的基础上选用ASHRAE推荐使用的地源热泵设计模拟软件GLHEPRO 3.0来进行30年运行模拟,分别对地下换热器尺寸的主要影响因素进行了系统性的综合分析,以期为地源热泵在我国的推广应用提供建议和参考。更多还原

【Abstract】 Energy source and environment become the important problems in every country all over the world with succeeding in applying the 2008 Olympic Games, and the utilization of clean energy becomes the important task for us especially. Ground-source heat pump systems have been widely applied to both residential and commercial heating and cooling in America and Europe as these systems can make significant contributions to reductions in electrical energy usage and have been recognized as an environmental-friendly alternative to conventional unitary system. However, this technology has seldom been adopted so far in our country. Many a work of research on GSHP and popularizing application need to be done. Vertical U-Tube ground-coupled heat pumps have become increasingly popular because of any outstanding advantage it has, such as: fewer area requirement, fewer limits, running steadily, better performance, lower costs on system maintenance etc.The characteristics of soil temperature distribution are studied at the beginning of the paper, and the computational model of original soil temperature field distribution is established for Guangzhou district. The temperature within 60m underground is simulated and the results are accorded with experimental data. Then, a three-dimensional model of the steady heat transfer around a single vertical U-tube for GSHP is established and the exit water temperature and the soil temperature distribution around the buried pipe running in winter are simulated, and the results are tallied with experimental data. In addition, the influencing factors based on the numerical method can be applied widely to confirm the extent of the buried-pipe outlet water temperature influenced by different circulate water storm and depth of well and different thermal conductivity of soil and rock around the buried-pipe and to analyze the influence of underground heat-exchanger’s heat transfer by different back-filled materials and different operation ways and different distances between the buried-pipes. It can offer reference of GSHP system running high effectively in a long time.Besides, the influence of the different dynamic heating and cooling load were calculated and simulated for the GCHP system. Comparing all the actual data, the simulation work were preceded by means of the relative software to prove the feasibility of the system. First, DeST is used to calculate the annual dynamic load. On the basis of monthly total cooling and heating loads and monthly peak cooling and heating loads, the main impact factors of vertical U-tube heat exchanger size and performance are simulated and analyzed through GLHEPRO3.0, recommended by ASHRAE as a good designing and simulating software for GCHPS, to carry on the task of simulation for 30 years. The purpose of doing this is to give some concrete suggestion and reference for the promotion of GCHPS in our country.更多还原