ABSTRACT
A research project was undertaken to obtain an understanding of the goaf gas distribution profiles near the tailgate area of the longwall goaf under 2 gateroad and 3 gateroad mining conditions for improved explosion risk management in gassy mines. Computational fluid dynamics (CFD) modelling studies were conducted and validated with operational longwall goaf gas distribution data. The results of the simulations indicated that there is a significant difference in the spread of explosive fringe (or close to explosive range) gas distribution profiles near the tailgate side of the longwall goaf under 2 gateroad and 3 gateroad conditions. The results indicated that under 3 gateroad conditions, explosive fringe gas distribution extends into the middle roadway between the longwall goafs thereby significantly increasing the area of explosive fringe distribution and likely relative increase in explosion risk. The details and results of various modelling investigations and recommended strategies for minimisation of the spread of explosive fringe gas distribution in the longwall goaf are presented in this paper.
