非稳态可控循环风系统瓦斯分布规律研究

DISTRIBUTION OF NONSTEADY METHANE IN A CONTROLLED RECICULATION SYSTEM

根据紊流传质理论建立了瓦斯浓度的纵向弥散模型及矿井通风系统的一维非稳定流动网络模型．根据该模型可以计算出可控循环通风系统内部任意位置、任意时刻的风量和瓦斯浓度值．应用该模型，对包含多个工作面的可控循环通风系统的各种非稳态现象进行了模拟分析，得出了瓦斯弥散作用对循环区瓦斯浓度的影响以及循环风机开启、关闭，风门关闭，瓦斯的非正常涌出等非稳态现象下循环区各分支瓦斯浓度的变化规律，为制定非稳态循环风系统的安全保障措施奠定了基础．

Based on theory of turbulent mass transfer a longitudinal methane dispersion model and a model of unidimensional nonsteady flow in mine ventilation network were established. The air quantity and methane concentration at any time in any position in the controlled reciculation system can be calculated by this model. Simulation analysis were made of various transient phonomena in a controlled reciculation system containing a multiple of work faces. The effect of dispersion on methane concentration and variation of methane concentration were obtained in all the branches of the reciculation system with various kinds of transient phenomena, such as start and stop of the fan, closing of air door, etc. This study has laid a foundation for taking safety measures in a nonsteady reciculation system.