Articles techniques et présentations

The most common way to exchange heat with the bedrock in Ground Source Heat Pump (GSHP) applications is circulating a fluid through a U-formed closed loop in vertical boreholes drilled several tenths of meters into the ground. This study presents and compares the results of eight cross sectional U-pipe Borehole Heat Exchanger configurations. Values from recent experimental temperature measurements and calculated heat transfer coefficients are used as boundary conditions. The two dimensional problem is solved with steady state heat transfer equations, and the net heat exchanged with the ground is obtained. The borehole thermal resistance is subsequently calculated and a quantitative comparison among all cases is presented.