2025 Center for Hydrogen Safety Asia-Pacific Conference
Detonation of Hydrogen–Air–Steam Mixtures in Large-Scale Industrial Installations
Author
Behdad Moghtaderi - Presenter, University of Newcastle
System failure in large-scale hydrogen-based installations such as electrolysers, fuel cells and storage facilities, may cause the formation of explosive hydrogen–air–steam mixtures. An in-depth understanding of the hazards of such mixtures under conditions pertinent to electrolysers, fuel cells (temperatures between 50 °C and 80 °C and pressures between 20 and 40 bar) and storage facilities is required before hydrogen-based installations can be designed and constructed. In this study, detonation properties of hydrogen–air–steam mixtures (e.g., detonation cell size) and their flame dynamics features (e.g., flame acceleration, runup distance, and deflagration-to-detonation transition “DDT”) were investigated experimentally and numerically to gain a more in-depth understanding of their hazards. While our results confirm the findings of previous studies in terms of the cooling effects of steam on detonation, we found that operating pressures between 20 and 40 bar counteract the effect of steam, making the hydrogen–air–steam mixture more detonable. This is particularly evident from the experimental data on detonation cell size and runup distance at pressures greater than 20 bar.