【作者】 雷飞；

【导师】 黄素逸；

【作者基本信息】 华中科技大学 ， 工程热物理， 2011， 博士

【摘要】 地源热泵空调系统利用地下浅层的低品位能量对建筑供热制冷,比常规空调系统能源利用更合理,是一项极具发展前途的可再生能源利用新技术。在国内节能减排形势下,地源热泵技术以其节能、环保特点,越来越受重视,近年快速发展。但地源热泵空调系统建设费用高,需通过其运行节能性来弥补。地源热泵的实际使用效果及性能,不仅与设备有关,还与地区和具体工程情况以及使用情况关系密切,这些影响因素是实验数据无法反映的。对运行使用的地源热泵系统进行测试和研究,是了解地源热泵系统运行特性与节能效果的重要手段。本文首先分别介绍了对两类地源热泵空调系统的全年运行监测分析。这两类系统分别是地埋管热泵和地下水水源热泵,是地源热泵空调系统的两种主要应用形式。两个系统都是武汉地区住宅建筑中使用的集中空调系统,使用条件相似、空调采暖规模相近。通过监测得出了系统和机组的季节能效性能系数,分析比较了地源热泵空调系统的温度情况,对地埋管系统由于冷热堆积效应的季节影响和年度影响进行了评价。验证了住宅建筑的能耗与室外空气温度的线性关系,说明在住宅建筑中度日法用于能耗负荷预测的适用性。并对这类系统存在的典型问题进行分析。结合全年运行监测分析,对地源热泵空调系统应用中的重点方面进行了专题研究,包括：对两个不同类型的地源热泵空调系统进行了深入的能效对比分析,分别与传统空调和地源热泵系统的文献数据进行比较,采用实测数据用理论模型预测理想能效,并与实测能效进行比较；对地下水源热泵空调系统,通过对最热月和最冷月的平均运行工况数据分析,得出了各设备及系统的火用损及火用效率,找出了系统的薄弱环节并对所提出的两种改进措施进行了对比,两种改进措施为：控制热泵机组端差、取消井水侧的换热器的直接连接方式；针对地下水源热泵中节能和地下水利用两方面问题,建立水源侧流量分析模型和典型的基准工况,分析板式换热器循环流量和地下水流量最佳范围,以及地下水取用单价的合理范围。在对地埋管换热器的传热分析基础上,本文提出了一种地埋管换热器的逆向建模方法：G函数插值法。利用地埋管换热器传热的线性叠加特点,采用约束非线性单纯形法求解反卷积计算,拟合模型参数。应用该方法进行了逆向建模与预测,并同基于正向模型DST的调试建模法进行了对比验证。模拟数据验证采用一个假设算例,合成热流做为全年热流输入负荷,附加随机噪声模拟数据测试和记录过程的误差,检验两种建模方法的容错性。实际运行数据验证采用两个不同规模的实际运行地埋管空调系统的运行数据进行逆向建模,验证建模方法的实用能力。小型系统运行数据来源于文献,大型系统为本文中的地埋管热泵监测数据。通过对大型系统第二年的温度预测与实测的对比,检验逆向模型的预测效果。验证计算结果显示：G函数插值法与DST调试法拟合预测结果较好,而G函数插值法拟合误差和预测误差都小于DST调试法,日记录数据误差是产生逆向建模拟合预测误差的主要原因。在G函数法基础上,本文又提出了一个简单的方法：度日G函数法。度日G函数法采用室外温度预测地埋管换热器负荷,适用于住宅类型建筑的集中空调系统。根据实测数据验证,度日G函数插值法比DST调试法误差大,但可满足工程应用的一般要求。本文通过对运行系统的实测,对地源热泵应用的关键问题进行了深入研究；建立了地埋管逆向模型,为地源热泵空调系统的运行应用提供了新的计算方法。更多还原

【Abstract】 Be using renewable geothermal energy in shallow ground layer, a ground source heat pump (GSHP) technology is known as one of air conditioning techniques which have the greatest developmental. The GSHP has great potentials in energy reduction and in reducing CO2 emissions to conventional HVAC systems. In China, energy shortage and environmental issues pose a serious challenge accompanied by rapid economic growth. GSHP has been spotlighted as both energy efficiency and environmental benefits. Generally, the initial investment for a GCHP system is higher than that of a conventional system. GCHP energy savings will offset the higher installing cost in future. However, there are many aspects affecting the actual amount of energy saved, such as climate, building load, ground heat exchanger, heat pump, control, etc. Recently, a lot of research on the energy performance of GCHP has been carried out. However, most of these previous research projects evaluated the performance of GCHP system based on a laboratory scale or a small capacity system. There is little data documenting the long-term performance of a large-sized GCHP. Evalution and research on real world installed GCHP will provide a more accurate understanding of the current technology’s performance.The paper presented that the energy performance evaluation of two types of GSHPs based on actual operational data. The two types of GSHPs were ground-coupled heat pump system (GCHPs) and groundwater heat pump system (GWHPs) which were, respectively, installed in two apartment buildings of Wuhan, China. In one year, we monitored various operating parameters, including the outdoor temperature, the flow rate, electrical consumption, and the water temperature. The coefficient of performance (COP) values of system and chiller were determined based on a series of measurements. During residential GCHP system operation, the heat injection rate into soil is larger than the heat extraction rate out of soil. The COP of chillers of the GCHPs decreased significantly during the heating season due to the lowering of ground soil temperature. The system power consumption exhibited a strong linear relationship with outdoor temperature in both seasons and this suggests that normalizing power consumption against degree-days is a highly practical index in energy analysis in resident buildings, especially in winter.Some research topics were studied on the two actual cases. An exergy analysis of a ground water heat pump system on the actual operation was conduced. The energy efficiency and exergy loss and efficiency in each of the components of the system are detemined for the average measured parameters obtained from the monitored results of the hottest month and the coldest month. Inefficient facts are found out and increased energy efficiencies of two proposed improvement measures were estimated. Lower approach temperature is effective energy saving. In addition to the energy analysis, a full exergy analysis helps to identify the components where inefficiencies occur. An economic analysis model for GWHP was established to calculate energy consumption and operating cost based on a baseline condition. Plate heat exchanger flow rate and groundwater flow rate were optimization parameters according to different water price of the groundwater:GWHP survey data shows the impact of water price on groundwater flow rate in design. The long-term energy performances of the GWHPs and the GCHPs were investigated and compared with conventional HVAC systems and other GSHPs on literature data. A performances model was established base on the two cases to constrast the predicted performance with the actual performance.Based on superposition theorem of geothermal heat exchangers (GHE), a inverse model for GHE, G-functions interpolation approach was proposed. Linear interpolation method was adopted to fit G-functions. The method presented here uses the Nelder and Mead simplex algorithm as part of a parameter estimation algorithm to estimate G-function. For verification of G-functions interpolation approach, a numerical experimentation had been conducted where synthetic load on GHE was established. The simulation results with error and no error, were inversely modeled by G-functions interpolation approach and DST calibrated approach. The actual dataset of a small sized and a large sized GSHPs were also used in inverse modeling to verify the results from the G-functions interpolation approach. The small sized GSHPs was from literature. The large sized vertical GSHPs was the monitored case in the paper. A detailed DST model of a GHE has been calibrated to monitored data. The second year predicted temperatures calculated by the two models were compared with the measured. The results show the two approaches are reliable and have good performance of error tolerance. The error of GHE water temperature calculated by G-functions interpolation approach was less than DST calibrated approaches. The data error inversely modeled was mainly from recorded day data. As a extension study of the G-functions interpolation model, degree-day G-functions approach was proposed. The model was based on degree-day prediction load and can be applied on the residential buildings. The standard deviation of GHE water temperature by degree-day G-functions approach was larger than DST calibrated approaches. The result shows the appropriateness of degree-day G-functions interpolation approach for the quantitative modeling of GHE.This paper shows that the research on actual performance according measured data and presents two inverse models:G-functions interpolation model, degree-day G-functions model approach, which provides new methods for GHE inverse modeling更多还原