Research on the optimal depth of medium and shallow single U-shaped buried pipe heat exchangers
LI Qianchang
ZHANG Wenke
YAO Haiqing
LIU Xia
ZHANG Shanshan
Abstract：The heat exchange capacity of the buried pipe heat exchanger varies nonlinearly with the increase of the drilling depth.When the drilling depth reaches a certain range,the heat extraction in winter continues to increase,but the heat dissipation in summer tends to level off or even decrease.Determining the optimal depth of the buried heat exchanger becomes an urgent problem to be solved.Three representative cities from typical climate zones in China are selected,namely Nanjing City in the hot summer and cold winter area,Jinan City in the cold area and Shenyang City in the severe cold area.The TRNSYS software is used to simulate and calculate the hourly cooling and heating load characteristics of buildings in each region throughout the year.Based on the established physical model and node equation,the single U-shaped buried heat exchanger is accurately solved.Under the premise of meeting the heating and cooling demands of buildings in three typical regions,the comprehensive performance of the buried pipe heat exchanger under different burial depths is analyzed by comprehensively considering factors such as heat exchange capacity,economy,and the soil temperature field on the borehole wall.The results show that the optimal burial depth of the single U-shaped buried heat exchanger is approximately 400 m.
Keywords：middle and shallow layerburied pipe heat exchangeroptimal depthheat exchange capacityeconomy
Publication Date：2025-09-25
Online Publishing Date：2025-11-10(First online date of this platform, not the publication date of the document)
Pages：6( 58-63 )