基于实验对4个不同形状的20L容器内的油气爆燃过程进行了研究,探讨了不同形状受限空间内爆炸压力荷载的变化和火焰行为的区别.结果表明:管道(短管和长管)的压力时序曲线较容积式受限空间(球形容器和立方体容器)的压力时序曲线更复杂,并且出现压力振荡;随着初始浓度的增加,超压值和平均升压速率均先增大后减小,在浓度为1.74%时达到最大值,此时,超压从大到小依次为:长管>短管>立方体>球形容器,平均升压速率从大到小依次为:短管>立方体>长管>球形容器;在爆燃初期,立方体中火焰行为为半球状层流火焰→扁平层流火焰,火焰速度先增大后减小,最大速度为12.5 m/s,长管中火焰行为为半球状层流火焰→拉伸指状火焰,火焰速度一直增大,最大速度为40 m/s.%The deflagration processes of gasoline-air mixture in four 20L vessels with different shapes were studied based on experiments, and the change of explosion pressure load and the difference of flame behavior in confined space with different shapes were discussed.The results showed that the pressure time-sequence curves of the tubes (short tube and long tube) were more complex than those of the volumetric confined space (spherical vessel and cubic vessel), with the appearance of pressure oscillation.The overpressure and the average rate of overpressure rise showed the same trend of increasing first and then decreasing with the increase of the initial concentration, and reached the maximum values when the concentration was 1.74%.At this moment, the sequence of the overpressure from large to small was long tube, short tube, cubic vessel and spherical vessel, and the sequence of the average rate of overpressure rise from large to small was short tube, cubic vessel, long tube and spherical vessel.In the early stage of deflagration, the flame behavior in the cubic vessel was the translation from hemispherical laminar flame into flat laminar flame, the flame velocity increased first and then decreased, and the maximum velocity was 12.5 m/s.While the flame behavior in the long tube was the translation from hemispherical laminar flame into stretched finger shape flame, the flame velocity increased continuously, and the maximum velocity was 40 m/s.
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