热渗耦合下的地埋管换热器管群排列方法研究

Research on group arrangement method of ground heat exchanger under coupled thermal conduction and groundwater seepage conditions

为了确定地源热泵工程中地埋管换热器管群的最优排列方法和管间距,建立了热渗耦合下的地埋管换热器管群三维传热模型。利用Fluent软件通过数值方法模拟了不同排列方法、不同管间距下的换热器出水口温度,着重研究了存在地下水渗流时管群排列方法对换热能力的影响,并且提出了管群单位面积换热量这一评价指标。研究结果表明,叉排管群的换热能力要高于顺排管群,地下水的渗流作用使之更加明显。无论是叉排还是顺排,管群的换热能力都和地下水渗流方向密切相关。

In order to determine optimal arrangement of ground heat exchangers and pipe spacing in actual ground source heat pump project, a three-dimensional heat transfer model of ground heat exchanger that couples thermal conduction with groundwater seepage is established in this paper. The numerical simulation method of Fluent is used to calculate heat exchanger outlet temperature at different arrangements and different spaces between pipes. The effect of group arrangement on heat transfer is emphatically studied at groundwater seepage condition, and an evaluation index of pipe group heat ex- changer capacity is put forward which names pipe group heat exchange per unit area. The simulation results show that the heat transfer capacity of staggered arrangement is higher than that of aligned arrangement,the groundwater seepage makes it more obvious. And no matter staggered arrangement or aligned arrangement, the heat exchanging capacity of pipe group is closely related with the groundwater seepage direction.