Research on the heat exchange characteristics of the deeply buried pipe type of energy pile

Abstract

Energy piles are a kind of building energy-saving technology that uses shallow geothermal materials. This article combines the existing ground source heat pump (GSHP) and inside buried pipe energy pile (IBP-EP) technology to develop a new type deeply buried pipe energy pile (DBP-EP) technology. It proposes construction technology based on postdrilling deeply buried pipe perfusion energy piles. Experiments and numerical studies on the heat exchange characteristics of DBP-EPs are carried out. The results show that the upper pile has a larger thermal radius and a higher heat exchange rate per linear meter than the lower deep wall. For models with the same heat exchange depth, the overall heat exchange of DBP-EP is higher than that of the GSHP. And the heat exchange rate per linear meter of the DBP-EP increases more significantly than that of the IBP-EP. By designing deep well heat exchange at the bottom of the pile, not only can the high thermal conductivity of the concrete of the pile foundation be fully utilized, but the overall heat exchange can also be effectively improved. This new type energy pile can be designed according to the heat exchange requirements to realize the efficient and economic utilization of geothermal resources.

Keywords

• Shallow geothermal
• Deeply buried pipe energy pile
• Temperature distribution law
• Heat exchange rate