Table 2 Simulation of key parameter settings.
Parameter | Value | Remarks | Parameter | Value | Remarks |
|---|---|---|---|---|---|
Average compressive strength (σc, MPa) | 10 | Experiments | Initial porosity of fractures (φf0) | 0.012 | Estimation |
Average tensile strength (σt,MPa) | 0.2 | Experiments | Dynamic viscosity of CH4 (µg, 10− 5pa·s) | 1.84 | [42] |
Average elastic modulus (E, GPa) | 4.8 | Experiments | Dynamic viscosity of water (µw, 10− 3pa·s) | 1.03 | [42] |
Poisson’s ratio of coal (ν) | 0.3 | Experiments | Adsorption volume constant of CH4 (VL, m3/kg) | 0.0256 | Experiments |
Initial permeability (k0, ×10− 17m2) | 2.56 | Experiments | Adsorption pressure constant of CH4 (PL, MPa) | 2.07 | Experiments |
Homogeneity index (m) | 9 | Estimation | Initial water saturation (sw0) | 0.6 | Field data |
Initial matrix porosity (φm0) | 0.065 | Experiments | Saturation of bound water (swr) | 0.32 | Estimation |
Standard atmospheric pressure (pa, MPa) | 0.1 | — | Initial pressure of CH4 (p0, MPa) | 0.8 | Field data |
