Numerical Study of Hydrogen Releases and Explosions in a Skid-Mounted Hydrogen Refueling Station

Many countries are developing hydrogen energy systems for fuel cell vehicles to embrace the low-carbon economy. Hydrogen refueling stations are one of the key infrastructure components for the hydrogen-fueled economy. Skid-mounted hydrogen refueling stations have smaller footprints and lower costs than traditional hydrogen refueling stations, so they can be more easily commercialized. The present work modeled hydrogen releases from a skid-mounted hydrogen refueling station using the flame acceleration simulation (FLACS) software. The hydrogen releases and dispersion were modeled for unintended leakages from the storage tube bundles of a skid-mounted hydrogen refueling station for 5 mm and 10 mm leak diameters in three different release directions. Hydrogen explosions were modeled for flammable clouds ignited at different instants after the hydrogen leakage. The results show that the hydrogen concentrations in the personnel operating area are lower than in other areas, but the flammable clouds still have an ignition risk. When the flammable cloud is ignited, both the people and the equipment suffer serious thermal radiation damage with additional damage due to the overpressures. When the hydrogen concentrations approach the stoichiometric ratio, the explosion will cause serious injuries to personnel and equipment inside the container. This work provides guidance for the structural design of skid-mounted hydrogen refueling stations.