The coalbed methane need to be exploited before coal mining through gas drainage, in order to obtain the dual purposes of lower coal mine accident rate and transfer gas into treasure. There is a strong fluid-solid coupling effect during the gas drainage processing. The seepage law of coal from Guzhuang mine of China at different gas pressure is tested, and its klingberg coefficients is obtained by curve fitting method. Based on the klingberg effect, the liquid-solid coupling effect of coal and gas is simulated through secondary development of ABAQUS software in this paper, in order to obtain the dynamic variation rule of gas pressure field and seepage field around the gas drainage hole. It provides a new quantitative method of determining gas drainage parameters and location. Numerical simulation results show that, during the processing of gas drainage, the stress field and seepage field are mutual influence and restriction, the gas pressure around the drainage holes is reduced and the coal seam stress relief, permeability increases, these play a prominent role in the effective preventing coal and gas outburst. Research results contribute to obtain accurate dynamic distribution law of the stress and seepage fields around gas drainage holes. It provides theoretical basis for optimizing gas drainage technology and raising gas drainage effect.Gas drainage is generally defined as the high concentration gas is extracted using gas pumps or other drainage device, and high density gas is discharged into the ground or the total return airway through the isolated pipe networkflj. The gas drainage is an effective measure for preventing coal and gas outburst, gas explosions and gas emission. The dual purpose with lower coal mine accident rate and transfer gas into treasure can be gotten. At present, China's coalbed methane exploitation is lagging behind. Theoretical research and effective analysis method about gas drainage technology design are rare [2-8]. As the gas pressure changes, the permeability of the coal body significant changes due to klingberg effect during the gas drainage process. It has important impact on the gas seepage. So the fluid-solid coupling effect has important impact on gas seepage during gas drainage process. The fluid-solid coupling law of gas and coal is analyzed using the ABAQUS software during gas drainage process. The research result of coupling effect of gas pressure field and stress field has important theoretical value and practical significance on revealing the mechanism of gas drainage preventing coal and gas outburst and field implementation of the gas drainage for preventing coal and gas outburst.
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