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煤与瓦斯突出产生的冲击气流有很强的破坏效应,首先分析了突出冲击气流的形成原因;然后建立了直巷道的几何结构模型,设定相应的初始条件与相关参数,对突出冲击气流的运动过程进行了数值模拟计算,得出了不同时刻的冲击气流压力、速度以及瓦斯相对质量浓度在巷道内的分布情况,同时分析突出发生区域出口断面处的冲击气流平均压力和速度随时间变化过程,并根据模拟结果得出定性与定量化的结论;最后,构建了煤与瓦斯突出在直巷中传播的实验系统,通过实验的手段分析了冲击波在直巷中衰减规律。研究结果表明,突出能在巷道空间内形成较高速度运动的冲击气流及冲击波;与突出区域原始瓦斯压力相比,冲击气流压力发生了急剧下降;冲击气流强度在断面不变的直巷道中传播会发生衰减,前期超压衰减较为缓慢,后期超压衰减增快。
Coal and gas outburst have a strong destructive effect on the impinging gas flow. Firstly, the reasons for the prominent impinging gas flow are analyzed. Then, the geometrical structure model of the straight roadway is set up, the corresponding initial conditions and relevant parameters are set, The numerical simulation of the moving process was carried out. The pressure, velocity and relative mass concentration of gas at different times were obtained. The mean pressure and velocity of the impinging flow at the outlet section of the outburst area were analyzed with time. Finally, the experimental system of coal and gas outburst propagating in straight lane was constructed. The attenuation law of shock wave in straight lane was analyzed by means of experiment. The results show that the striking can form the impact airflow and shock wave with higher velocity in the tunnel space. Compared with the original gas pressure in the protruding area, the pressure of the impinging stream sharply drops. The intensity of the impinging stream propagates in the straight lane with constant cross-section Attenuation occurs, pre-over-pressure attenuation is more slow, post-over-pressure attenuation faster.