空腔体积比对甲烷爆炸冲击波传播机制的影响

Influence of cavity volume ratio on propagation of methane blast wave

为探究空腔相对体积比的变化对甲烷爆炸冲击波抑制作用的影响,采用计算流体力学(CFD)软件和大型圆管甲烷爆炸试验系统研究空腔相对体积比对甲烷爆炸冲击波的影响。结果表明:腔体相对体积比由4. 8变为7. 9,空腔对峰值超压消减作用增强,火焰持续光照强度消减作用骤然增强;腔体相对体积比增加到12. 7时,拟合得到火焰持续光照强度衰减因子呈现"L"衰减关系,整体火焰持续光照强度消减基本趋于稳定,火焰持续光照强度衰减率由90. 8%变为90. 9%;峰值超压衰减因子衰减先慢后快;腔体相对体积比为12. 7时抑爆效果最佳,整体火焰持续光照强度衰减率90. 9%,峰值超压衰减率30. 8%。

In order to study influence of relative volume ratio change of cavity on suppression of gas explosion shock wave,experiment was carried out by using Computational Fluid Dynamics( CFD) software and large-scale circular tube methane explosion test system. The results show that cavity’s reduction effect on peak overpressure is strengthened as its relative volume ratio changes from 4. 8 to 7. 9,and continuous light intensity reduction of flame is suddenly enhanced. When the ratio increases to 12. 7,fitting results indicate that attenuation factor of flame continuous light intensity presents a "L"curve,general reduction tends to be stable, and attenuation rate rises from 90. 8% to 90. 9%. Attenuation factor of peak overpressure is slow at first and then fast. It is found that cavity’s explosion-suppressing effect is the best when its relative volume ratio reaches 12. 7 with an general attenuation rate of continuous light intensity at 90. 9% and and that of peak overpressure at 30. 8%.