Enhancing safety in hydrogen refuelling stations: computational analysis of hydrogen explosion hazards

This paper aims to enhance the understanding of hydrogen explosions in hydrogen refuelling stations and evaluate associated risk factors using computational fluid dynamics simulations. The model is first validated against the measured data for hydrogen dispersion and explosion. Different scenarios are then modelled to understand the ignition timing and location. The study estimates acceptable distances to minimize asset damage and human injury from explosion incidents. It has been found that higher wind speeds lead to faster and more extensive dispersion of the hydrogen gas released during a leak. In addition, since strong wind can act as a powerful driving force for the shock wave, the impact of the explosion is found to be less. Interestingly, moving the source of ignition to regions with higher hydrogen concentration has a marginal impact on overpressure and temperature; however, the blockage ratio can significantly amplify the overpressure. It is found that cases with high blockage, including storage room, and cases with large volumes of flammable cloud, including leakage from compressor towards the ground, have the highest hazards. The findings will provide valuable insights into fire and explosion prevention in various areas of hydrogen refuelling stations and contribute to safer hydrogen infrastructure construction.