摘要
为了研究障碍物结构对预混甲烷管道内火焰传播速度和峰值超压的影响,自行设计一套火焰加速系统。在火焰加速管道上安装光电传感器和压力传感器分别测定火焰传播速度和超压,试验中选取5种结构障碍物,即平板、长方体、三棱柱、四棱柱和圆柱,其阻塞比分别为20%,40%和60%3种。研究结果表明:初始阶段障碍物阻碍火焰传播,当火焰越过障碍物后,障碍物能显著加速火焰传播。随着阻塞比增加,相同结构障碍物的火焰传播速度总体上不断增加,而峰值超压先变大后减小。相同阻塞比下,平板、三棱柱对火焰传播速度和超压影响相对较大;长方体居中;圆柱、四棱柱对增加火焰传播速度和超压作用相对较小。较小阻塞比障碍物管道内超压与无障碍物管道中的超压相比显著增加,但此后,管道中超压随阻塞比变化不明显。
By applying self-designed experimental system for flame acceleration and choosing five different structure obstacles,the effect of obstacle structure on flame propagation speed and peak overpressure for premixed methane flame propagation was investigated.Plates,cuboids,triple prisms,quadruple prisms,cylinders were adopted with a blockage ratios of 20%,40% and 60%,respectively.Pressure transducers and photoelectric diodes were mounted at different positions of top acceleration tube for measuring flame speed and overpressure.Results show that flame propagation is deterred at the initial stage and then is accelerated after flame front has come across obstacles.With the blockages ratios augment,flame speed of the identical structure obstacles increases continuously as a whole,while overpressure rises at first and then reduces.To the same blockage ratios,plates and triple prisms have a larger influence on the flame speed and overpressure;cuboids are intermediate;effects of quadruple prisms and cuboids are comparatively limited.Compared with no obstacles in the tube,obstacles aggrandize overpressure in tube even though its blockage ratios are low,but after that,the overpressure does not take on a distinct change with the change of blockage ratios.
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2011年第2期63-67,共5页
China Safety Science Journal
关键词
障碍物结构
火焰传播速度
峰值超压
火焰加速
阻塞比
obstacle structure
flame propagation speed
peak overpressure
flame acceleration
blockage ratios
