障碍物压力反射特性对瓦斯爆炸传播影响的数值模拟研究*

为了研究不同形状障碍物对瓦斯爆炸传播的影响机理，对直径0.2 m、长6.5 m的密闭直管道内的瓦斯爆炸过程进行数值模拟。研究结果表明:在该实验条件下，对于火焰通过整个管道的时间，方形障碍物时间最长，球形障碍物与无障碍物时间接近，且用时最短；无障碍物时，在反射压力波作用下火焰传播速度存在明显的波动特性；有障碍物时，障碍物的诱导作用要大于反射压力波的作用，火焰传播的这种波动特性得到抑制，提升了火焰前锋向未燃区域传播的能力；压力波的波动频率与气流震荡、压力波反射叠加有关，波幅则主要与正向压力波和反射压力波的叠加效果有关。研究结果为煤矿瓦斯爆炸事故防治及隔抑爆技术应用提供技术支撑。

Numerical simulation research on influence of obstacle pressure reflection characteristics on gas explosion propagation

In order to study the influence mechanism of obstacles with different shapes on the propagation of gas explosion,the numerical simulation on the gas explosion process in a closed straight pipe with the diameter of 0.2 m and the length of 6.5 m was conducted.The results showed that for the time of flame passing through the entire pipe under the experimental conditions,the time of square obstacle was the longest,and the time of spherical obstacle and without obstacle were close and the shortest.When there was no obstacle,the flame propagation velocity fluctuated obviously under the action of reflected pressure wave.When there was an obstacle,the induction effect of obstacle was greater than that of the reflected pressure wave.The fluctuation characteristic of flame propagation was suppressed,and the ability of flame front propagating to the unburned area was improved.The fluctuation frequency of pressure wave was related to the airflow oscillation and pressure wave reflection superposition,and the amplitude was mainly related to the superposition effect of forward pressure wave and reflection pressure wave.The research results provide technical support for the prevention and control of coal mine gas explosion accidents and the application of explosion suppression technology.