采空区失稳过程中冲击气浪灾害的动力响应特性

Dynamic Response Characteristics of Shock Air Wave Disaster in Gob Failure Process

为探索采空区顶板失稳灾害演化过程的动力学行为,针对某矿井采空区顶板整体切落的失稳形式,建立了流固耦合力学模型,利用Matlab得到了失稳后采空区内风速和风压的演化规律。利用FLUENT软件,获得了冲击气浪沿巷道传播的纵向风速以及横截面处流速分布情况,进而揭示冲击气浪灾害动力学特性。结果表明:随着顶板下落高度的增加,采空区内风速经历了加速和减速2个阶段,风压曲线可以分为缓慢上升阶段和类指数上升阶段,冲击气浪流速沿巷道纵向随着距离增大呈负指数函数减小,巷道横截面流速分布分为左侧高流速区和右侧低流速区,巷道横截面左侧底角处风速最大。

To explore the dynamic behavior of the evolution process of the roof instability in gobs,a fluid-structure coupled mechanical model was established for the instability of the whole roof cut-off in a mine,and the evolution of wind speed and wind pressure in instable gob was obtained using Matlab.By using FLUENT software,the longitudinal wind speed and the velocity distribution at the cross section of the roadway propagated by the shock air wave were obtained,so as to reveal the dynamic characteristics of the shock air wave disaster.The results show that with the increase of the falling height of the roof,the wind speed in the gob has experienced two stages of acceleration and deceleration.The wind pressure curve can be divided into a slow rising stage and an exponential rising stage.The impulse gas velocity along the roadway longitudinally follows the distance.The increase shows a decrease in negative exponential function,and the cross-sectional flow velocity distribution of the roadway is divided into the left high flow velocity area and the right low velocity flow area.The wind speed at the left bottom corner of the cross section of the roadway is the largest.