地下水渗流对单孔地埋管换热器换热性能影响的数值模拟
Numerical simulation on influence of groundwater seepage on heat exchange performance of single-borehole ground heat exchangers
摘要：
建立了二维地下水渗流条件下地埋管换热器的数值计算模型，对单孔地埋管换热器周围的土壤温度场进行了数值模拟。为了验证数值模拟方法的可行性，将模拟结果与地下水渗流条件下的移动线热源理论解析解进行了对比，结果显示，当R=0.5和2.5时，模拟结果的相对误差分别为0.72%和5.42%，具有较高的精确度。模拟结果表明，当贝克来数Pe＜6时，即地下水渗流速度小于3×10-7 m/s（9.46 m/a）时，可以忽略地下水渗流产生的对流换热的影响。
Abstract：
Establishes a numerical calculation model for the heat exchange performance of ground heat exchanger in two-dimensional groundwater seepage condition, and simulates the temperature field of soil around single-borehole ground heat exchangers.In order to validate the effectiveness of the numerical method,compares the simulation result with the analytical solution based on moving linear heat source theory in groundwater seepage condition. The result shows that the relative error is 0.72% and 5.42% When R is 0.5 and 2.5 respectively, so there is a good agreement with the analytical solution. The simulation results show that when Pe is less than 6, namely, the groundwater seepage velocity is less than 3×10-7 m/s（9.46 m/a）, the influence of the convention heat transfer caused by groundwater seepage can be ignored.
Keywords:groundwaterseepage,groundheatexchanger,heatexchangeperformance,numericalsimulation,seepagevelocity,soiltemperaturefield,ground-sourceheatpump