EDEM-FLUENT coupled simulation of coal-gas outburst two-phase flow

In the process of coal-gas outburst, the gas-solid two-phase flow of pulverized coal and gas will induce large-scale damage to underground mining. In this work, in order to study the dynamic evolution law of gas-solid two-phase flow of coal-gas outburst, and clarify the short-time destructive effect of outburst dynamic phenomenon, an EDEM-FLUENT coupled model is constructed to realize the numerical simulation of coal-gas outburst two-phase flow. The simulation results show that the flow velocity of pulverized coal in a short time (tens of milliseconds) approaches to the maximum velocity rapidly, which can reach 60 m/s. The velocity of pulverized coal is inversely proportional to the particle size. The initial acceleration of particles is slow, and then the acceleration increases rapidly. The accumulation angle of pulverized coal in the outburst hole is about 21° and is far less than the natural accumulation angle of pulverized coal, which is consistent with the general phenomenon of coal-gas outbursts. The results also show that the shock wave overpressure of the coal-gas outburst of numerical simulation is similar to that of the physical simulation test, and the difference is less than 10%. And the pressure change in the roadway is completed in short time. In terms of spatial relationships, the pressure at the position closest to the outburst mouth is not the maximum, and the maximum pressure exists at a certain position away from the outburst mouth.