苯蒸气爆炸/燃烧火焰传播特性研究

为探究苯蒸气爆炸/燃烧火焰传播特性,在自主设计加工的长度1 m的透明可视化爆炸试验管道内,开展不同浓度苯蒸气的爆炸/燃烧试验,利用高速摄像仪拍摄管道内不同浓度苯蒸气爆炸火焰传播图像,并对比研究火焰图像。结果表明:低浓度苯蒸气-空气预混气体点燃后发生剧烈爆炸反应,随着苯蒸气浓度的升高,剧烈爆炸反应转为温和燃烧反应;火焰传播平均速度随苯蒸气浓度的增大而增大,在苯蒸气体积分数为2. 8%时,火焰传播平均速度达到最大值,之后,随着苯蒸气浓度的增大而减小;低浓度苯蒸气爆炸火焰传播过程经历了急剧加速、急剧减速、缓慢加速和缓慢减速4个阶段,高浓度苯蒸气火焰传播速度基本保持不变,火焰形态与火焰传播速度密切相关。

Study on propagation characteristics of benzene vapor explosion and combustion flame

In order to explore the propagation characteristics of explosion and combustion flame of the benzene vapor,explosion and combustion experiments of different concentrations of benzene vapor were carried out in a self-designed 1 m transparent explosion test pipeline. The high-speed camera was used to capture images of flame propagation of benzene vapor explosion in the pipeline. The flame images were compared and analyzed. The results show that a violent explosion reaction occurs when the low concentration of premixed benzene vapor-air gases are ignited,and the violent explosion reaction turns into a mild combustion reaction with the increase of concentration of benzene vapor in the premixed gases. The average flame propagation velocity increases with the rise of benzene vapor concentration,and reaches a maximum when the volume fraction of benzene vapor is 2. 8%. Then the velocity decreases with increasing benzene vapor concentration. The propagation process of explosion flame of low concentration benzene vapor can be divided into four stages: a rapid accelerating stage,a rapid decelerating stage,a slow accelerating stage and a slow decelerating stage. The propagation speed of high-concentration benzene vapor flame basically keeps constant,and the flame shape is closely related to flame propagation speed.