This study examines the influence of polyurethane porous materials and carbon dioxide on hydrogen/air explosions within an enclosed vessel. Through analysis of peak overpressure, maximum rate of pressure rise, and shock wave propagation velocity, the suppression effects on explosions in hydrogen-air mixtures with different equivalence ratios at room temperature and atmospheric pressure are investigated. Findings indicate that porous materials with a PPI (pores per inch) of 60 significantly mitigate hydrogen/air explosions across all equivalence ratios. Conversely, a PPI below 60 exacerbates the explosions. Simultaneous presentation of PPI60 porous material and a CO addition level of x = 2 (carbon dioxide to oxygen ratio) reduces hydrogen explosion pressure to only 13.7 kPa at "Φ = " 1.2, representing an attenuation rate of 84% and falling well below the human safety threshold of 28 kPa. Independent effects of carbon dioxide and porous materials on hydrogen explosions across various equivalence ratios are also explored. The experimental design encompasses a broad range of equivalence ratios, covering hydrogen's explosive limits. These results contribute to the design of flame arrestors and enhance understanding of explosion suppression in hydrogen systems.

中文翻译：

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聚氨酯泡沫和二氧化碳对抑制氢气/空气爆炸的影响

本研究探讨了聚氨酯多孔材料和二氧化碳对封闭容器内氢气/空气爆炸的影响。通过峰值超压、最大压力上升速率和冲击波传播速度的分析，研究了室温和大气压下不同当量比的氢气-空气混合物对爆炸的抑制效果。研究结果表明，PPI（每英寸孔径）为 60 的多孔材料可在所有当量比下显着减轻氢气/空气爆炸。相反，PPI 低于 60 会加剧爆炸。同时使用 PPI60 多孔材料和 x = 2（二氧化碳与氧气之比）的 CO 添加水平，在“Φ =” 1.2 时将氢气爆炸压力降低至仅 13.7 kPa，衰减率为 84%，远低于人类压力安全阈值为 28 kPa。还探讨了二氧化碳和多孔材料对不同当量比的氢气爆炸的独立影响。实验设计涵盖了广泛的当量比，涵盖了氢的爆炸极限。这些结果有助于阻火器的设计，并增强对氢气系统爆炸抑制的理解。