Energy Piles

This paper depicts physical procedure of heat transfer in energy pile foundations, which support the building structure and provide heating and cooling for the building. The energy piles exchange heat energy with the soil by a working circulating fluid in a vertical borehole Ground Source Heat Pump (GSHP) system. The advantages of energy piles are more cost-effective and environmentally friendly. The aim of this study is to develop three-dimensional (3D) transient numerical heat transfer model in multiple borehole heat exchangers (BHE) by means of computer code. The 3D numerical model that combines finite volume method (FVM) and finite element method (FEM) is proposed. One-dimensional (1D) model is adopted for the working fluid flow within the pipe to simplify the calculation process. Then, through a comprehensive correlation, the experimental results are utilized to verify the numerical model. The differences between the simulation data and the testing results are less than 10%.