正方形泄放口尺寸对高压氢气泄漏激波传播与自燃特性的影响研究

Effect of square opening area on the shock wave and spontaneous ignition of high-pressure hydrogen released into a tube

实验研究了高压氢气从不同尺寸泄放口释放到管道中的激波传播特性和自燃发生规律,采用了三种尺寸的正方形泄放口,面积分别为113 mm^(2)(开口率λ=4/5),75 mm^(2)(λ=2/3),49 mm^(2)(λ=1/2)。结果表明,开口率的减小会削弱管道内激波的强度和传播速度,并抑制激波在向下游传播过程中的发展。同时发现,随着开口率的减小,氢气自燃所需的最小泄放压力增大。进一步,当开口率减小时,氢气自燃的整体火焰强度减弱,火焰传播速度减小。特别是在开口率较小的条件下(λ=1/2),当泄放压力增大时,管道内最大火焰强度未有明显增长,表明开口率减小对整体火焰强度有一定的抑制作用。

An experimental study investigated the shock wave propagation characteristics and spontaneous ignition of high-pressure hydrogen released into the tube through releasing ports with different opening areas.Three sizes of square openings are considered,with an area of 113 mm^(2)(opening ratioλ=4/5),75 mm^(2)(λ=2/3),and 49 mm^(2)(λ=1/2).The results show that reducing the opening ratio weakens the intensity and speed of the shock wave in the tube,further inhibiting the development of the shock wave propagating downstream.Moreover,the minimum burst pressure required for hydrogen spontaneous ignition increases with the decreasing opening ratio.When the opening ratio decreases,the overall flame intensity and propagation speed of hydrogen spontaneous ignition decrease.Especially when the opening ratio is small(λ=1/2),when the burst pressure increases,the maximum flame intensity in the tube does not have an apparent increase,indicating that the reduction of the opening ratio has an inhibition effect on the overall flame intensity.