管道截面对氢气/空气预混爆炸影响的实验研究

为研究管道截面对氢气/空气预混火焰形状与传播速度的影响,选用三个长度都为1m而截面尺寸不同的方形管道进行实验。实验结果表明,在截面为80mm×80mm的管道中,四种氢气浓度下预混火焰都发展形成了郁金香火焰。火焰传播速度呈现上升,下降,再上升的波动。在截面为100mm×100mm和150mm×150mm的管道中,只有在氢气浓度20%下形成郁金香火焰,并且传播速度也出现上述的波动。而在氢气浓度25%,30%,40%下,预混火焰都呈指尖形传至管口,未出现郁金香火焰,传播速度都是不断上升。三个管道对比中,截面为100mm×100mm的管道内火焰平均传播速度最快,且压力波第一峰值最大。

Experimental study of the duct cross section effects on the hydrogen/air premixed explosion

An experimental study of the duct cross-section effects on hydrogen-air premixed explosion flame shape and propagation speed is presented by using three different cross-section ducts with a length of 1000 mm. The experimental results showed that the tulip flame formed under all of four hydrogen volume fractions in the duct of 80 mm×80 mm cross-section, and the propagation speed had the trend of first rising, then falling, and rising again. The tulip flame formed only under the hydrogen volume fraction of 20% in the ducts of 100 mm×100 mm and 150 mm×150 mm cross-section, and the propagation speed showed the same trend as above. In these two ducts, the flames propagated to the nozzle with fingertip shapes under the hydrogen volume fractions of 25%, 30%, 40%, and the propagation speeds rise continually. Comparing the three ducts, the fastest flame propagation and the largest explosion pressure appeared in the duct of 100 mm×100 mm cross-section.