Abstract: Accuracy of heat transfer model is directly related to the computational accuracy of heat transfer efficiency of energy pile, which influences the design of energy piles. Taken energy pile with buried spiral pipe as the research object, an in-situ test was conducted in Xinyang area, Henan province. Then, measured data such as temperature field around the pile was acquired, and calculation results of the cylindrical heat source model and the coil heat source model are respectively compared with measured data. Research results show that the computational accuracy of heat source model with finite length is higher than that of heat source model with infinite length. Coil heat source model with finite length is more accurate than cylindrical surface heat source model with finite length. The calculation error of tube wall temperature in coil heat source model with finite length is less than 1.5%, the calculation error of temperature field around the pile is less than 2.5%, and the water temperature at inlet and outlet of buried pipe less than 2.2%, respectively. In view of this, coil heat source model with finite length is recommended for calculating temperature field in energy pile with spiral buried tube. The applicability of different heat transfer models for the spiral pipe pile was explored, and can be taken as reference for the design of energy pile with buried spiral tube.

Key words: energy pile with buried spiral pipe, cylindrical heat source model, coil heat source model, temperature field around pile, temperature field around the energy pile, experimental verification