Abstract:

The characteristics of synags/air mixture explosion in half-open and closed ducts with various hydrogen fractions at the stoichiometric were comparatively studied by a self-made laboratory experimental facility. The results show that there is a significant difference in the premixed flame propagation structure of syngas explosion in open and closed pipelines. In the closed duct, the classic tulip flame is observed from all hydrogen fractions, and the distorted tulip flame can be observed at the hydrogen fraction of 70% and 90%, respectively. In the half-open duct, the classic tulip flame forms at hydrogen fraction of 10%, 30%, and 50%,respectively, and the distorted tulip flame can be observed at the hydrogen fraction of 10% and 30%,respectively. Both in half-open and closed duct, the flame propagation speed and maximum pressure increases with the hydrogen fraction increase. When the hydrogen fraction is low (f < 50%), the flame propagation speed and maximum pressure increase rapidly as hydrogen fraction increases, and at higher hydrogen fraction (f ≥ 50%), the flame propagation speed and maximum pressure increase slowly with increasing hydrogen fraction.

Key words: syngas, explosions, hydrogen, tulip flame, distorted tulip flame

摘要：

通过自主搭建的小尺寸实验平台，对比研究了当量比为1时不同氢气体积分数下，预混合成气在开口和闭口管道中的爆炸特性。研究结果表明：开口和闭口管道中合成气爆炸预混火焰传播结构具有明显差异；在闭口管道中，在所有的氢气体积分数下均观测到经典郁金香火焰结构，其中氢气体积分数为70%和90%时，能够观测到扭曲的郁金香火焰结构；在开口管道中，仅在氢气体积分数为10%、30%、50%时形成了经典郁金香火焰，且当氢气体积分数为10%、30%时，出现了扭曲郁金香火焰。开口和闭口管道中的火焰传播速度和爆炸压力峰值均随着氢气体积分数的增加而增大。当氢气体积分数较低（f < 50%）时，火焰传播速度和爆炸压力峰值随着氢气体积分数的增大而迅速增大，而在较高氢气体积分数（f≥ 50%）时，随着氢气体积分数的增加，火焰传播速度和爆炸压力峰值增加缓慢。

关键词: 合成气, 爆炸, 氢, 郁金香火焰, 扭曲郁金香火焰