Fig. 4
From: Thermally driven fracture aperture variation in naturally fractured granites
Experimental setup. The injection of deionized water through the fractured granodiorite cores is carried out by Pump 2 at a constant fluid flow rate. The effluent fluid enters Pump 3 at a constant outlet pore-fluid pressure, \(P_{\text{fo}}\). Pump 1 sets the axial and radial confining pressures, respectively, \(P_{\text{co}\_\text{a}}\) and \(P_{\text{co}\_\text{r}}\)