障碍物对油气-空气混合气体泄压爆炸火焰传播特性影响

为了研究障碍物对油气泄压爆炸火焰传播特性的影响规律，进行了不同数量障碍物工况下的对比实验，并利用纹影仪和高速摄影仪记录了火焰传播过程，针对障碍物对火焰形态、火焰锋面位置及火焰传播速度的影响规律进行了研究，结果表明:圆柱体障碍物会导致油气泄压爆炸火焰形态产生褶皱和弯曲变形，诱导层流火焰向湍流火焰转变，加速火焰的传播，对油气泄压爆炸火焰的初始传播形态有显著影响；随着障碍物数量的增多，火焰锋面传播距离点火端的最大距离增大，但到达最远距离的时间减少；障碍物能够增强火焰的传播速度，尤其对障碍物下游火焰影响最为显著，随着障碍物数量的增多，火焰传播的最大速度也随之增大，但达到最大火焰传播速度的时间却随之减少；障碍物的存在增大了油气泄压爆炸过程外部爆炸压力，并且随着障碍物数量的增多，外部爆炸压力峰值增长幅度增大。

Effect of obstacles on flame propagation characteristics of vented explosion by gasoline-air gas mixture

In order to investigate the effect of obstacles on the flame propagation characteristics of vented explosion by gasoline-air mixture, a series of contrast experiments were carried out under the conditions of obstacles with different amount. The schlieren and high-speed camera were applied to record the flame propagation process, and the influence laws of obstacles on the flame shape, flame front location and flame speed were studied. The results showed that the cylindrical obstacles can cause the wrinkle and bending deformation of flame shape, induce the transition from laminar flame to turbulent flame, and accelerate the flame propagation, with significant effect on the initial propagation shape of gasoline-air vented explosion flame. The maximum distance of flame front spreading away from the ignition source increases with the increasing amount of obstacles, while the time to reach the farthest distance becomes shorter. The obstacles can enhance the flame propagation speed, especially for the downstream flame of obstacles with the most obvious effect. The maximum flame propagation speed increases with the increasing amount of obstacles, while the time to reach the maximum flame propagation speed becomes shorter. The obstacles increase the external explosion pressure during the gasoline-air vented explosion process, and the increasing range of external explosion pressure peak increases with the increasing amount of obstacles.