Numerical Simulation of Methane Accumulation in Roof Falling Zone of Roadway in Coal Mine

Methane usually accumulates in roof falling zone forming severe hazard to production safety of coal mine. This paper adopts FLUENT, a Computational Fluid Dynamics software, to simulate numerically local methane accumulation in roof falling zone. The research mainly discusses the influence of wind velocity on methane accumulation. It shows that the accumulated-methane concentration decreases with the increase of wind velocity. However, wind current with above a critical speed can not weaken gas accumulation dramatically. The simulation results also make it clear that the vertical and oblique wind deflectors set up in roof falling zone will both dilute accumulated-methane significantly owing to the great changes of wind flow. In addition, the dilution effect of the former is better than that of the latter. The simulation works not only verify the operational methane accumulation prevention measures to be reasonable and scientific but also provide theoretical support for practical operation.