Mining Publication: CFD Modeling of Fire Spread Along Combustibles in a Mine Entry

A computational fluid dynamics (CFD) program was applied to fire spread along combustibles in a ventilated mine entry. The rate of flame spread was evaluated for the ribs and roof of a coal mine entry, timber sets, and a conveyor belt. The CFD program models char-forming materials with temperature-dependent thermal properties. The program solves three-dimensional time-dependent flow equations with a mixture fraction model for the gas phase reactions. Radiant heat exchange is evaluated for non-scattering gas. The CFD program predicted a flame spread rate of 0.0145 m/sec for an actual coal mine fire in which the estimated flame spread rate was 0.0086 m/sec. This overestimated flame spread rate was a possible consequence of the presence of inert materials in the mine entry's roof and ribs. CFD fire spread rate predictions of 0.043 m/sec and 0.73 m/sec bounded the measured value of 0.27 m/sec for fire spread along Douglas-fir timber sets in a tunnel.