立体结构障碍物对甲烷预混火焰传播影响的研究

Study on the Influence of Solid Obstacles on Premixed Methane Flame Propagation

使用自行设计的火焰加速试验系统,研究了3种立体结构障碍物对管道内预混火焰传播速度和超压的影响。选用长方体、正四棱柱和圆柱,其阻塞比均为40%。结果表明,管道内障碍物对火焰传播的初始阶段起阻碍作用,当火焰越过障碍物后,障碍物加速火焰传播过程。有障碍物时管道内最大火焰传播速度和峰值超压比无障碍物时要大。随着点火距离的增大,管道中最大火焰传播速度和超压先变大后减小。当障碍物位于约6倍管径处时,对管道中火焰传播速度和超压影响最大。点火距离的改变对火焰传播速度的影响大于对管道内超压的影响。

The influence of solid obstacles in tube on propagation speed and overpressure of premixed flame was studied with a self-designed flame acceleration test system,3 kinds of solid structure obstacles,such as cuboids,quadrangular and cylinder were respectively used with the same blockage ratio of 40 percentage.The results show that obstacles deter flame propagation at initial stage on flame process,but accelerate flame propagation process after flame gets across the obstacles.The maximal flame speed and overpressure with obstacles in tube are larger than those without obstacles in tube.With the ignition distance increasing,the maximal flame speed and overpressure in the tube first increase and then decrease.When obstacles set at the place of 6 times of tube diameters,they have the most influence on flame speed and overpressure.The effect of the change of ignition distance on flame speed is much larger than that on overpressure.