开口率和点火源类型对汽油蒸气泄压爆炸内场超压荷载的影响

Effect of vent size and the ignition source type on the internal overpressure loading of vented gasoline-air mixture explosion

构建了汽油蒸气泄压爆炸实验系统,研究了开口率和点火源类型对汽油蒸气泄压爆炸过程中内场超压荷载的影响规律,研究结果表明:汽油蒸气泄压爆炸会导致内场形成多个超压峰值,其中最大峰值由泄压爆炸膜破坏所形成;随开口率的增大,P1数值近似呈线性下降,P2的数值近似呈指数下降,外场火焰的Rayleigh-Taylor不稳定强度增加,Helmholtz振荡的持续时间延长;点火源类型对最大超压峰值和平均升压速率大小均有影响,不同点火源类型下超压峰值和平均升压速率的数值从大到小排列分布依次为高温灯丝>火药点火杆>高能电火花>明火点火杆;火焰结构为"火焰外锋面+内部火焰核心",二者所占的比例受点火源类型的影响。

The gasoline vapor venting explosion experimental system was established,and a series of tests were conducted to investigate the effects of opening rate and the ignition type on the internal overpressure loadings during the process of vented explosion.The results showed that during vent explosion proeess,the multi overpressure peaks phenomenon appeared,and the maximum overpressure peak was caused by the burst of the vent cover.With the increase of the vent size,the value of P1 decreases linearly,the value of P2 decreases exponentially,the intensity of R-T instability and the duration of Helmholtz oscillation increases.The value of maximum overpressure peak and average rate of pressure rise size was affected by ignition source type.The value of maximum overpressure and the average rate from large to small was high temperature ignition rod,powder ignition source,ignition spark,open firing point.The flame structure included an outer flame front and an inner flame core,and the proportion of the two structures was affected by the type of ignition source.