基于垂直U型埋管换热器的圆柱源理论及其应用研究

基于经典常热流圆柱源理论，引入叠加原理与负荷累积思想将其发展为能够适用于长时期短时间步长变热流地源热泵系统模拟的变热流圆柱源模型，并引用实例从理论与实验两方面对改进模型的有效性进行了验证。将圆柱源理论模型应用于太阳能-土壤源热泵系统联合供暖运行性能的数值模拟，结果表明：对于青岛地区，太阳能-土壤源热泵联合供暖运行模式相比地源热泵单独运行节能8．3％。14．5％，就各运行模式而言，带有蓄热水箱的联合运行模式二效果最佳；通过优化进一步得出：其设计可按能量比例63％与37％或尺寸比例13．8m（埋管）/m^2（集热器）来分别确定盘管长度与集热器面积的大小；至于系统经济性，只有当单位面积集热器价格小于5．81m埋管所需费用时，SESHPS在经济上才是可行的。

Study on Cylindrical Source Theory Based on Vertical U-Tube Ground Heat Exchangers and It's Application

Based on classic constant heat flux Cylindrical Source Theory,the variable heat flux Cylindrical Source Model of Vertical U tube was developed to simulate short time step long-term operation performance of GSHPS operating in variable heat transfer rate by quoting the idea of superposition principle and load aggregation. The present model was verified theoretically and experimentally with citing examples. The numerical simulation of heating performance of a Solar-earth source heat pump was performed with the improved Cylindrical Source model. The results indicate that the energy-saving rate of SESHPS is 8.3%-14.5% compared with ground source heat pump (GSHP) for application in Qingdao. The combined operation mode 2 with water tank in which the heated water flows through the solar collector first and then through the buried coil is preferable. The area of solar-collector and the length of buried ground coil can be calculated respectively either by the energy ratio of 63% to 37% or by size ratio of 13.8m to 1m2. In addition,SESHPS may be economically viable only when the price of solar collector per square meters is smaller than the drilling cost of 5.81 m length.