基于土壤源热泵的太阳能跨季节蓄能的理论研究与实践

发布时间：2018-02-03 22:52

本文关键词： 土壤源热泵系统太阳能跨季节蓄能地埋管传热模型 TRNSYS模拟　出处：《天津大学》2014年博士论文　论文类型：学位论文

【摘要】：利用土壤源热泵进行太阳能跨季节蓄能可以有效地解决土壤源热泵系统土壤热失衡的问题。对于寒冷和严寒等热负荷占优的建筑气候区,本文针对基于土壤源热泵的太阳能跨季节蓄能机理、跨季节蓄能实践的可行性、蓄热系统的设计、蓄热周期的预测、蓄热过程的TRNSYS模拟分析、蓄热系统的匹配运行测量调试等问题开展系列研究。以一个实际工程为支撑,开展了跨季节蓄能的实践。首先,分析利用土壤源进行太阳能跨季节蓄能的可行性。建立双U型地埋管传热的物理模型和数学模型,利用Matlab软件对理论模型进行求解计算,得到土壤温度分布曲线和拟合方程,通过温度分布法计算得到地埋管换热器传热量。结果表明,地埋管换热器的换热量能够满足蓄热量的要求。其次,根据天津工业大学新校区A区设备站2010年、2011年和2012年土壤源热泵系统的运行能源账单和天津地区典型气象年的太阳能辐射数据,同时考虑太阳能利用率、极端天气、管路热量损失等因素,预测蓄热实验周期,设计蓄热实验系统并进行蓄热实验。蓄热实验分别测量了实验周期内的太阳能辐射强度、集热水箱供回水温度及流量、地埋管附近各层土壤实时温度,通过计算分别得到蓄热期内的太阳能辐射量、地埋管蓄热量和土壤温升等数据,利用太阳能利用率和延迟响应的概念分析了辐射量和蓄热量之间关系。实验中,总辐射量为956991.3MJ,总蓄热量为480299.1MJ,总蓄热量是地埋管年均取热量的2.03倍,总蓄热量占总辐射量的50.2%,太阳能平均利用率为50.2%。再次,利用TRNSYS模拟软件解决了过渡季节的跨季节蓄能难题。建立仿真模型,并利用实验数据对该模型进行验证,提出相关的误差修正模型,用来消除气象参数和设备耗散热对模拟结果的影响。过渡季节的蓄热过程模拟结果表明,尽管在过渡季节,其储热量(247719.47k Wh)同样能够满足蓄热量的要求。最后,从土壤温度、蒸发器进水温度、系统和机组COP及经济环境性四个方面对蓄热效果进行了评价。根据2010年、2011年,2012年冬季土壤源热泵的能源账单,计算得到系统和机组的COP值,结果表明:在没有蓄热模式的情况下,土壤源热泵系统和机组的COP值是逐年下降的;进行蓄热实验后,系统和机组的COP有小幅度的提升,分别提升3.4%和2.4%。
[Abstract]:The use of ground-source heat pump for cross-seasonal solar energy storage can effectively solve the problem of soil heat imbalance in ground-source heat pump system. In this paper, the mechanism of cross-seasonal solar energy storage based on ground-source heat pump, the feasibility of cross-season energy storage practice, the design of heat storage system, the prediction of heat storage cycle, and the TRNSYS simulation analysis of heat storage process are discussed. A series of research is carried out on the matching operation, measurement and debugging of heat storage system. Based on a practical project, the practice of cross-season energy storage is carried out. First of all. The feasibility of using soil source to store solar energy across seasons is analyzed. The physical and mathematical models of heat transfer of double-U buried pipes are established, and the theoretical model is solved by Matlab software. The soil temperature distribution curve and fitting equation are obtained, and the heat transfer quantity of the underground tube heat exchanger is calculated by the temperature distribution method. The results show that the heat transfer of the ground buried tube heat exchanger can meet the requirement of heat storage. According to the operating energy bill of the ground-source heat pump system on 2010, 2011 and 2012, and the solar radiation data of the typical meteorological year in Tianjin area, the equipment station in area A of the new campus of Tianjin University of Technology is used. At the same time, solar energy utilization, extreme weather, pipe heat loss and other factors are taken into account to predict the experimental cycle of heat storage. The thermal storage experiment system was designed and heat storage experiment was carried out. The solar radiation intensity, the temperature and flow rate of the collecting water tank and the real time temperature of each layer of soil near the buried pipe were measured respectively. The data of solar radiation, buried pipe heat storage and soil temperature rise during the storage period were calculated, and the relationship between solar radiation and heat storage was analyzed by using the concepts of solar energy utilization ratio and delayed response. The total amount of radiation is 956991.3 MJ, the total heat storage is 480299.1 MJ, the total heat storage is 2.03 times of the average annual heat of buried pipe, and the total heat storage is 50.2% of the total radiation. The average utilization rate of solar energy is 50.2. Thirdly, the TRNSYS simulation software is used to solve the problem of inter-seasonal energy storage in the transition season. The simulation model is established, and the experimental data are used to verify the model. A related error correction model is proposed to eliminate the influence of meteorological parameters and equipment heat dissipation on the simulation results. Its heat storage can also meet the requirements of heat storage. Finally, from the soil temperature, evaporator inlet temperature. The heat storage effect was evaluated from four aspects of system and unit COP and economic environment. According to the energy bill of ground-source heat pump in the winter of 2010 2011 2012. The COP value of the system and the unit is calculated. The results show that the COP value of the GSHP system and the unit decreases year by year without the heat storage mode. After the heat storage experiment, the COP of the system and the unit were raised by 3.4% and 2.4, respectively.
【学位授予单位】：天津大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TU83;TU17

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