Thermally driven fracture aperture variation in naturally fractured granites

Geothermal Energy

Science – Society – Technology

Table 1 Specimen properties

Specimen	L (mm)	w (mm)	Fracture type	\({b}_{\text{mean}}\) (mm)	\(\sigma\) (mm)	\({L}_{\text{c}_\text{x}}\) (–)	\({L}_{\text{c}_\text{y}}\) (–)
N14	49.7	25.0	Tensile	0.184	0.122	0.02	0.04
N19	46.0	24.5	Tensile	0.414	0.132	0.08	0.06

Physical properties of the specimens under investigation, where L and w are the length and width of the aperture field of the specimen, respectively, \(b_{\text{mean}}\) and \(\sigma\) are the mean and the standard deviation of the aperture distributions, respectively, \({L}_{\text{c}_\text{x}}\) is the normalized correlation length in the flow direction, and \({L}_{\text{c}_\text{y}}\) is the normalized correlation length in the direction perpendicular to the flow