Numerical Simulation of Coal Spontaneous Combustion around a Borehole Induced by Negative Pressure Gas Drainage

Figure 4

Change law of the oxygen concentration at different monitoring points for suction pressures of (a) 18 kPa, (b) 23 kPa, (c) 30 kPa, and (d) 35 kPa.

(a)

(b)

(c)

(d)