Liu Qiqi, Liu Zhenyi, Peng Shiyao, Liu Chuang, Liu Changqi, Liu Luoqian, Zhou Rui, Zhi Shujie, Fan Tao, Li Pengliang
State Key Laboratory of Explosion Science and Safety Protection, Beijing Institute of Technology, Beijing 100081, China.
General Institute of Science and Technology Research, PipeChina, Hebei 071799, China.
ACS Omega. 2024 May 21;9(22):23853-23863. doi: 10.1021/acsomega.4c01876. eCollection 2024 Jun 4.
To evaluate the explosion hazard of CH/H mixtures, experiments were conducted in a long and closed pipeline with a length-to-diameter ratio of 51 and built-in obstacles, and the characteristic parameters of deflagration shock waves were analyzed under different hydrogen blending ratios (0 ≤ λ ≤ 100%) and equivalence ratios (0.5 ≤ Φ ≤ 3). The results indicate that within the range of Φ = 0.8-1.2, the explosion overpressure ( ) exhibits a "two-zone" structure distribution. When 0 ≤ λ ≤ 80%, shows an initial increase and then a decrease in both regions, while deflagration to detonation transition (DDT) occurs in the second evolution region when λ = 100%, which is caused by the different strengths of the positive feedback mechanism coupled with flames and shock waves. The , (d/d), and show a trend of first increasing and then decreasing and monotonically increasing with the increase of the equivalence ratio and hydrogen blending ratio, respectively, and reach their maximum values at Φ = 1.0 and λ = 100%. For CH/H mixtures with low hydrogen blending ratios (λ = 0 and 20%), the and (d/d) in the fuel-lean conditions (Φ = 0.9 and 0.8) are higher than those in the fuel-rich conditions (Φ = 1.1 and 1.2), while the CH/H mixtures under high hydrogen blending ratios (λ = 80 and 100%) are the opposite. Overall, the increase in H at a high hydrogen blending ratio and the increase in the equivalence ratio at a fuel-lean condition significantly enhance the average . In addition, chemical kinetics analysis found that R38 and R52 elementary reactions are the dominant elementary reactions that promote and inhibit temperature increase, respectively. Their temperature sensitivity coefficients are negatively correlated with the hydrogen blending ratio and positively correlated with the equivalence ratio. The research results provide vital information for evaluating the explosion hazards of CH/H mixtures and developing safety protection measures.
为评估CH/H混合物的爆炸危险性，在长径比为51且内置障碍物的长封闭管道中进行了实验，并分析了不同氢气混合比（0≤λ≤100%）和当量比（0.5≤Φ≤3）下爆燃冲击波的特征参数。结果表明，在Φ = 0.8 - 1.2范围内，爆炸超压（ ）呈现“两区”结构分布。当0≤λ≤80%时，两区的 均呈现先增大后减小的趋势，而当λ = 100%时，在第二个演化区发生爆燃向爆轰转变（DDT），这是由火焰与冲击波耦合的正反馈机制强度不同所致。 、（d/d）和 分别呈现先增大后减小以及随当量比和氢气混合比的增加单调增大的趋势，并在Φ = 1.0和λ = 100%时达到最大值。对于低氢气混合比（λ = 0和20%）的CH/H混合物，贫燃条件（Φ = 0.9和0.8）下的 和（d/d）高于富燃条件（Φ = 1.1和1.2），而高氢气混合比（λ = 80和100%）的CH/H混合物则相反。总体而言，高氢气混合比下H的增加以及贫燃条件下当量比的增加显著提高了平均 。此外，化学动力学分析发现，R38和R52基元反应分别是促进和抑制温度升高的主要基元反应。它们的温度敏感系数与氢气混合比呈负相关，与当量比呈正相关。研究结果为评估CH/H混合物的爆炸危险性和制定安全防护措施提供了重要信息。
