This study employs numerical simulation to establish a heat transfer model for a group of double U-shaped borehole heat exchangers (BHEs)
incorporating the influence of groundwater seepage. The evolution patterns of the seepage field and ground temperature field are analyzed
along with a sensitivity assessment of key seepage-related factors affecting heat transfer performance. The results reveal that in the absence of groundwater seepage
thermal interference between adjacent BHEs leads to significant cold accumulation in the central region
impairing heat transfer efficiency. However
the presence of seepage substantially mitigates cold accumulation. Along the direction perpendicular to seepage flow
thermal interference between BHEs is negligible
with heat transfer influence oscutting only from upstream to downstram alony the seepage direction. Sensitivity analysis indicates that the thickness of the seepage layer has the most pronounced impact on BHE heat transfer efficiency
followed by seepage velocity
while the seepage direction exhibits the weakest influence.
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