Optimization of Indirect Fracturing Process Parameters Based on Mechanical Properties of Fractured and Low-Permeability Coal

Figure 9

Results of experiments and simulation. (a) Specimen [21]. (b) Simulation results of HF opening displacement (left, unit: m) and fracture pattern of 3# specimen (right, [21]) (stress state: σ_v, σ_H, σ_h = 6, 5, 3 MPa. (c) Water pressure-time curves at injection injection point obtained from results of simulation and experiments (3# specimen). (d) Simulation results of HF opening displacement (left, unit: m) and fracture pattern of 5# specimen (right, [21]) (Stress state: σ_v, σ_H, σ_h = 9, 5, 3 MPa). (e) Pressure-time curves at water injection point obtained from numerical simulation and HF experiments (1# specimen).

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