The effect of boundary layer wind flow in roadway on the methane motion
The wind velocity boundary layer must be formed near the roadway wall due to the viscous effect.In the study on the motion law of methane in the roadway to date,the wind velocity is mostly assumed to be uniform.In order to assess the effect of wind velocity gradient on the motion and accumulation of methane,the motion of methane emitted from wall in 2D roadway space is simulated with a dispersion model in this paper.The simulated results show that the emitted methane will form an accumulation layer near the roof and the methane concentration decreases with the distance from the roof in an exponential law.The concentration profile in the accumulation layer has two sections: one is a certain distance adjacent to the wall where the methane concentration is constant,another one is the distance farther from the wall where the methane concentration declines with the distance in an exponential curve.Comparing the simulated methane motion in the uniform wind flow with that in the boundary layer wind flow,the simulated methane concentration at former condition is distinctly smaller than that at latter condition.It is concluded from these simulations that the un-uniformity of the boundary layer wind flow in the roadway has a great effect on the methane motion and can not be neglected.
Boundary layer Methane Wind velocity Roadway
Xing Mao
Institute of Mining Technology,Taiyuan University of Technology,Taiyuan 030024,China PR
国际会议
The 2007 International Conference on Mine Hazards Prevention and Control(2007矿山灾害预防与控制国际学术会议)
青岛
英文
142-146
2007-10-17（万方平台首次上网日期，不代表论文的发表时间）