Study on Parameters Optimization of High Level Extraction Boreholes in Rock Burst Seam

For the optimization of high level borehole parameters, improving the effect of gas control in upper corner of rock burst coal seam, taking 5304 working face in Tangkou Coal Mine as engineering background, the methane extraction models of different high level borehole parameters were analyzed by fluid simulation software FLUENT. The numerical results show that the optimal effect of methane extraction can be achieved when terminating height of high level borehole is 27 meters and it is six times that of the mining thickness, and drilling 2 holes in each drilling field. Field practice shows that the maximum return air gas volume fraction at working face is 0.56%, the average value was 0.39%.