中文摘要：

为研究瓦斯浓度对封闭型管道内爆炸波振荡特征的影响,用数值模拟方法分析超压波形振荡特征、超压沿管道的变化和浓度对振荡周期的影响。研究结果表明：随着瓦斯体积分数的增加,超压峰值和振幅先增大后减小,体积分数在9.5%时,具有最高的爆炸超压和最强的振荡特性。瓦斯体积分数在接近爆炸上下限时均出现多重爆炸波的振荡叠加现象,爆炸超压最大值既能发生在反射端,也能发生在爆炸波的对冲叠加点。随着瓦斯体积分数的增加,振荡周期先变短后变长,在体积分数为9.5%时具有最短的周期;振荡周期可以用拟合得到的关于浓度的多项式来计算。

英文摘要：

Oscillation characteristics of overpressure wave, the changing of overpressure along the pipe- line and the influence of gas concentration on oscillation period in a closed end pipe were studied based on the simulation method. The results show that with the increase of gas methane, overpressure peak and amplitude undergo a changing process of decreasing, then increasing; when the fraction is 9.5% , the overpressure reaches its peak and the oscillation experiences the most intense process; whenever the frac- tion reaches the lower explosion limit or the upper explosion limit, the phenomenon of oscillation and su- perposition appear in multiple explosion waves; the maximum of explosion overpressure is likely to appear at the reflection end or appear at the superposition point of blast waves ; with the increase of fraction, oscil- lation period undergoes a changing process of decreasing, then increasing; the period is the shortest when the fraction is 9.5% ; oscillation period can be calculated by the polynomial about the fraction.