Study on Air Leakage Law in Gob of Shallow Buried Coal Seam Under Forced Ventilation

The 12206 working face of Huojitu Coal Mine was taken as the research object. Combining the distribution of “vertical three-zones” in gob with the “O” type caving compaction in the gob and the nonlinear seepage theory, a three-dimensional distribution model of the permeability in the gob was established. The Fluent, a CFD (Computational Fluid Dynamics) software, was used to simulate the air leakage law from working face to the gob. The result indicates that the energy of the working face is larger than the surface in shallow buried coal seam with forced ventilation, and so the air of the working surface leaks to the surface through the gob. And the distribution of the air leakage flow field in the gob is similar to the shape of “O” in the horizontal direction and is similar to the shape “bathtub” in the vertical direction. The influence of energy difference between the working face and surface on air leakage in gob is simulated. The results show that the higher the energy difference between the working face and surface, the greater the air leakage volume between the gob and surface, and the relationship between energy difference and air leakage volume is exponential function.