为研究小尺度管道中CH4-O2爆炸火焰传播规律,设计并建立了小尺度管道实验系统,由小尺度管道、配气系统、点火系统、爆炸压力数据采集系统、高速摄影系统以及数据处理系统等组成.利用小尺度管道实验系统,研究了不同初始压力、不同初始浓度条件下CH4-O2混合气体爆炸火焰传播的规律.爆炸火焰传播速度由高速摄影系统采集的图像利用Matlab程序进行处理并计算得到.结果表明:同一初始浓度条件下,随着初始压力的增加,爆炸火焰在管道中传播的最大速度随之增大;管道中爆炸火焰最大速度与初始压力的倒数近似呈线性关系;对于不同初始浓度下的混合气体,都存在使混合气体形成加速火焰的最低初始压力;以化学当量浓度(CH4+2O2)为界限,当初始浓度越接近化学当量浓度时,混合气体形成加速火焰所需的最低初始压力越小.
To study on the explosive flame propagation of CH4-O2 in small scale pipeline, a small scale pipeline experimental system was designed and built, including a small scale pipeline, gas distribution system, ignition system, explosive pressure data acquisition system, high-speed photography system and data processing system. The law of CH4-Oz explosion flame propagation under different initial pressure and initial concentration was studied by using small scale pipeline experiment system. The images collected by high-speed photography system were processed and calculated by the Matlab program to get the speed of explosive flame. The results show that, with the increase of the initial pressure, the maximum velocity of the explosive flame in the pipeline increases. The maximum velocity of the explosion in a pipe is linear with the reciprocal of the initial pressure. For different initial concentrations of mixed gas, there is a minimum initial pressure to form an accelerating flame. The minimum initial pressure to form an accelerating flame is smaller when the initial concentration is close to the equivalent concentration.