Numerical and experimental analysis of jet release and jet flame length for qualitative risk analysis at hydrogen refueling station

The advent of eco-friendly hydrogen vehicles has prompted attempts to increase the installation of hydrogen refueling stations in urban areas; however, sufficient safety measures have yet to be established. Gas plume dispersion, jet flame, and heat flux were investigated using HyRAM software by considering accidents at hydrogen refueling stations in reports published by Sandia National Laboratories. Hydrogen release and jet flame length were measured using the Schlieren imaging system and a thermal imaging camera. The HyRAM simulation analysis results were more conservative than the experimental results. These showed that the pressure and leak diameter greatly influenced the safety of hydrogen facilities. Individual and societal risks were analyzed through RISKCURVES, and the risks were found to be highest in the sidewalk and dispenser. An F-N (Frequency- Number of fatalities) curve to verify the risk of installing a hydrogen refueling station in urban areas was derived, and the safety distance from residents was proposed.