不同封闭情况下T型管道中瓦斯爆炸传播规律实验研究*

为研究不同封闭情况下T型管道中瓦斯爆炸的传播规律，在90°分岔管道中进行瓦斯爆炸实验，管道封闭情况为弱封闭（双PVC薄膜弱封闭）和强封闭（直管封闭或支管封闭）。实验结果表明:在瓦斯浓度为9.5%时，管道中各点处的瓦斯爆炸压力、火焰传播速度和火焰锋面振荡幅度最大，11%次之，8%最小。T型管道中，弱封闭端瓦斯爆炸压力不断减小；火焰传播速度先缓慢增大后减小，随后又快速增大。强封闭端，瓦斯爆炸压力增大；火焰传播速度先缓慢增大后略微下降，随后快速增大后又大幅度下降，甚至出现火焰锋面振荡现象。不同封闭管道中各测点的瓦斯最大爆炸压力和火焰传播速度大小比较可知，直管封闭管道＞双PVC薄膜弱封闭管道＞支管封闭管道。

Experimental study on propagation laws of gas explosion in T-shaped pipe under different enclosed conditions

In order to study the propagation laws of gas explosion in the T-shaped pipe under different enclosed conditions,the gas explosion experiments were carried out in 90° bifurcated pipe,and the enclosed conditions of pipe were the weak closure (double PVC film weak closure) and the strong closure (straight pipe closure or branch pipe closure).The results showed that when the gas concentration was 9.5%,the oscillation amplitudes of gas explosion pressure,flame propagation velocity and flame front at each point in the pipe were the largest,followed by 11%,and that of 8% was the smallest.In the T-shaped pipe,the gas explosion pressure at the weak closure end decreased continuously.The flame propagation velocity increased slowly at first,then decreased,and then increased rapidly.At the strong closure end,the gas explosion pressure increased,the flame propagation velocity increased slowly at first and then decreased slightly,and increased rapidly and then decreased sharply,and even the flame front oscillated.The maximum gas explosion pressure and flame propagation velocity of each measuring point in different enclosed pipes were compared,and the sequence was: straight enclosed pipe > double PVC film weak enclosed pipe > branch pipe enclosed pipe.