办公建筑土壤源多源复合热泵系统能效特性研究
发布时间：2018-08-21 20:50
【摘要】：地埋管换热器作为土壤源热泵系统最大的换热部件，它的换热性能直接影响到整个土壤源热泵系统的能效特性。而办公建筑间歇性使用特点，以及土壤源热泵系统的使用受土壤吸放热平衡所限制，使得土壤源热泵需要添加其它辅助散热设备，这又决定了办公建筑冷、热负荷及地埋管换热器负荷分配特性，最终影响到土壤源多源复合热泵系统的能效性能。本课题就影响土壤源多源复合热泵系统能效特性的原因进行深入研究，提出能效较高的新型土壤源多源复合热泵系统。 本课题根据地埋管换热器传热机理建立计算模型，以地埋管换热器钻孔井壁为界，将地埋管换热器分为钻孔内部模型与钻孔外部模型，钻孔内部采用解析计算模型，钻孔外部采用数值计算模型。对钻孔外部模型进行对称性分析，简化了钻孔外部计算模型，减少了所要计算的次数。 以都市之门2012年夏季工况土壤源热泵实测放热量作为钻孔外部编程计算的输入值，采用MATLAB软件对所建立的模型进行编程计算，将地埋管换热器出口温度编程计算值与实测值进行比较，剔除由于开机时刻不稳定运行导致的误差之后，平均误差为1.7%，误差均在5%以内，验证了所建立地埋管换热器模型的正确性。 根据西安典型气象年数据对某待建办公项目采用DeST软件进行全年动态负荷计算，在基本满足地埋管换热器吸放热平衡的条件下进行负荷分配，通过对地埋管换热器全年8760个小时的编程计算，得到全年运行后土壤平均温度仅升高了0.19℃，保证了地埋管换热器的换热性能。 办公建筑间歇运行对改善地埋管换热器的换热效果起到了重要作用，地埋管换热器出口温度在冬/夏工况都没有出现低温/高温报警，系统安全性能高。停机11个小时后，冬"夏季工况，井壁温度分别修复了2.65"2.16℃。无论是夏季工况还是冬季工况，运行一个周期24小时，土壤温度场仅升高或降低0.02℃，，次日整个土壤温度与当日温度基本持平。 本文提出了土壤源与污水源双源复合的创新型热泵系统，同时就该热泵系统原理进行了说明。并且得到：冬季工况，土壤源与污水源双源复合热泵系统较传统空调供暖系统节能30%。夏季工况，土壤源与污水源双源复合热泵系统较传统冷却塔系统节能11.9%；较土壤源+冷却塔系统节能9.5%。为办公建筑空调系统的设计可以提供一定的参考。
[Abstract]:As the largest heat transfer component of the ground-source heat pump system, the heat transfer performance of the ground heat exchanger directly affects the energy efficiency characteristics of the whole ground-source heat pump system. However, the intermittent use characteristics of office buildings and the use of ground-source heat pump system are limited by the equilibrium of soil heat absorption and heat release, which makes the ground-source heat pump need to add other auxiliary heat dissipation equipment, which determines the cooling of office buildings. Heat load and load distribution characteristics of underground heat exchanger will affect the energy efficiency of multi-source heat pump system. In this paper, the causes of affecting the energy efficiency characteristics of the ground-source multisource heat pump system are studied, and a new type of ground-source multi-source heat pump system with high energy efficiency is proposed. According to the heat transfer mechanism of the underground tube heat exchanger, the paper establishes the calculation model. Taking the borehole wall of the ground buried tube heat exchanger as the boundary, the ground buried tube heat exchanger is divided into the borehole internal model and the borehole external model, and the analytic calculation model is used in the borehole interior. The numerical calculation model is used for the outside of the borehole. The symmetry analysis of the borehole external model simplifies the borehole external calculation model and reduces the number of times to be calculated. Taking the measured heat emission from ground-source heat pump in the summer of 2012 as the input value of the external programming calculation of borehole, the model was programmed by MATLAB software. By comparing the calculated value of the outlet temperature of ground buried tube heat exchanger with the measured value, the average error is 1.7, and the error is less than 5% after eliminating the error caused by unstable operation at the start time. The correctness of the model is verified. According to the typical meteorological data of Xi'an, the DeST software is used to calculate the annual dynamic load of an office project to be built, and the load distribution is carried out under the condition of basically satisfying the heat balance of heat absorption and discharge of the underground tube heat exchanger. By programming 8760 hours a year, it is found that the average temperature of soil is only increased by 0.19 鈩
本文编号：2196316
[Abstract]:As the largest heat transfer component of the ground-source heat pump system, the heat transfer performance of the ground heat exchanger directly affects the energy efficiency characteristics of the whole ground-source heat pump system. However, the intermittent use characteristics of office buildings and the use of ground-source heat pump system are limited by the equilibrium of soil heat absorption and heat release, which makes the ground-source heat pump need to add other auxiliary heat dissipation equipment, which determines the cooling of office buildings. Heat load and load distribution characteristics of underground heat exchanger will affect the energy efficiency of multi-source heat pump system. In this paper, the causes of affecting the energy efficiency characteristics of the ground-source multisource heat pump system are studied, and a new type of ground-source multi-source heat pump system with high energy efficiency is proposed. According to the heat transfer mechanism of the underground tube heat exchanger, the paper establishes the calculation model. Taking the borehole wall of the ground buried tube heat exchanger as the boundary, the ground buried tube heat exchanger is divided into the borehole internal model and the borehole external model, and the analytic calculation model is used in the borehole interior. The numerical calculation model is used for the outside of the borehole. The symmetry analysis of the borehole external model simplifies the borehole external calculation model and reduces the number of times to be calculated. Taking the measured heat emission from ground-source heat pump in the summer of 2012 as the input value of the external programming calculation of borehole, the model was programmed by MATLAB software. By comparing the calculated value of the outlet temperature of ground buried tube heat exchanger with the measured value, the average error is 1.7, and the error is less than 5% after eliminating the error caused by unstable operation at the start time. The correctness of the model is verified. According to the typical meteorological data of Xi'an, the DeST software is used to calculate the annual dynamic load of an office project to be built, and the load distribution is carried out under the condition of basically satisfying the heat balance of heat absorption and discharge of the underground tube heat exchanger. By programming 8760 hours a year, it is found that the average temperature of soil is only increased by 0.19 鈩
本文编号：2196316
本文链接：https://www.wllwen.com/kejilunwen/sgjslw/2196316.html
