Numerical simulation on easy self-ignition of fully mechanized coal face the goaf spontaneous combustion control

In Gushan coalmine,the fire areas of small coal mine and upper coal seam exist in the top of 065-2 fully-mechanized caving face with large inclination and easy self-ignition coal.Moreover,spontaneous combustion period is only 15 days,so both of them contribute to especial difficulty of fire prevention in working place.Gob gas composition is ascertained by the way of sampling tests after laying beam tubes under the gob area in this study.Then according to the distribution of gob gas concentration,spontaneous ignition "three bands" are divided and the smallest value of advancing of working face is calculated as 2.54 meters.Because of this heavy workload and long testing period,and gob ponding easily lead laying equipments to inaccurate or even damaged.In view of this,by numerical simulation,using Comsol software to simulate the distribution of oxygen concentration in goaf,verifying the simulated oxygen concentration with measured oxygen concentration in the goaf.The result turns out to be feasible for the simulatin of oxygen concentration distribution in goaf based on Comsol.It provides reliable theoretical guidance for easy self-ignition of fully mechanized coal face the goaf spontaneous combustion control in the future.