For spontaneous combustion possibilities under large flux methane drainage in the goal, dynamic permeability in combination with the Forchheimer nonlinear equation was used to solve the problem of 3D oxygen distributi...For spontaneous combustion possibilities under large flux methane drainage in the goal, dynamic permeability in combination with the Forchheimer nonlinear equation was used to solve the problem of 3D oxygen distribution, heating law in goaf and to forecast the effects of fire protection by taking the fifth section face of the No. 18 coal seam in Nanshan Coal Mine as the basis for this study. The results demonstrate that if the vertical position of the drainage laneway is so low as to cause serious air leakage, a high oxygen concentration area exists in the return side of the goaf, and there is also a high temperature region which has faster heating rate than in the other areas. The effect of methane drainage on goal heating can be alleviated dramatically by simultaneous plugging and nitrogen injection. The results show that gas data in the return side of the goaf must be detected carefully in the work face, which is of similar drainage arrangement. Therefore, comprehensive fire protection measures should be carried out if conditions permit.展开更多
In view of the deficiency of current gas monitoring systems in coal mine roadwayexcavation, a two-level information fusion technology, which adopted the adaptiveweighted algorithm and the BP neural network technology,...In view of the deficiency of current gas monitoring systems in coal mine roadwayexcavation, a two-level information fusion technology, which adopted the adaptiveweighted algorithm and the BP neural network technology, was applied to gas monitoring.The results show that the adaptive weighted algorithm can realize self-regulation by decreasingthe weight value of the failed sensor automatically, so as to eliminate the effect ofthe failed sensor and ensure the effectiveness and accuracy of the gas monitoring system.The BP neural network can not only effectively predict the gas gush quantity of the excavationroadway, but also accurately calculate the gas concentration in the region whereone or more sensors have failed, so as to provide the basis for judging the safety status ofthe roadway excavation.The experiments prove the superiority and feasibility of the applicationof information fusion in gas monitoring.展开更多
文摘For spontaneous combustion possibilities under large flux methane drainage in the goal, dynamic permeability in combination with the Forchheimer nonlinear equation was used to solve the problem of 3D oxygen distribution, heating law in goaf and to forecast the effects of fire protection by taking the fifth section face of the No. 18 coal seam in Nanshan Coal Mine as the basis for this study. The results demonstrate that if the vertical position of the drainage laneway is so low as to cause serious air leakage, a high oxygen concentration area exists in the return side of the goaf, and there is also a high temperature region which has faster heating rate than in the other areas. The effect of methane drainage on goal heating can be alleviated dramatically by simultaneous plugging and nitrogen injection. The results show that gas data in the return side of the goaf must be detected carefully in the work face, which is of similar drainage arrangement. Therefore, comprehensive fire protection measures should be carried out if conditions permit.
基金Supported by the National Natural Science Foundation of China(50874106)the National High Technology Research and Development Program of China(2007AA06Z114)
文摘In view of the deficiency of current gas monitoring systems in coal mine roadwayexcavation, a two-level information fusion technology, which adopted the adaptiveweighted algorithm and the BP neural network technology, was applied to gas monitoring.The results show that the adaptive weighted algorithm can realize self-regulation by decreasingthe weight value of the failed sensor automatically, so as to eliminate the effect ofthe failed sensor and ensure the effectiveness and accuracy of the gas monitoring system.The BP neural network can not only effectively predict the gas gush quantity of the excavationroadway, but also accurately calculate the gas concentration in the region whereone or more sensors have failed, so as to provide the basis for judging the safety status ofthe roadway excavation.The experiments prove the superiority and feasibility of the applicationof information fusion in gas monitoring.
