Thermal Performance Analyses of Multiborehole Ground Heat Exchangers

Table 2

Experimental data [26].

Borehole depth	75 m
Borehole spacing	9 m
Borehole diameter	114 mm
U-tube inner diameter	21.8 mm
U-tube outer diameter	26.7 mm
Undisturbed ground temperature	17.3°C
Ground thermal conductivity	2.3 W/m-K
Ground volume specific heat	2012 kJ/m^3-K
Borehole thermal resistance	0.1622 m-K/W
Fluid flow rate	0.631 kg/s