Study on the Explosion of the Hydrogen Fuel Tank of Fuel Cell Electric Vehicles in Semi-Enclosed Spaces

The rise in hydrogen fuel cell electric vehicles (FCEVs) is expected to pose a variety of hazards on the road. Vehicles using hydrogen could cause significant damage, owing to hydrogen vapor cloud explosions, jet fires caused by leakage, or hydrogen tank explosions. This risk is expected to further increase in semi-enclosed spaces, such as underground parking lots and road tunnels. Therefore, it is necessary to study the fire safety of hydrogen vehicles in semi-enclosed spaces. In this study, an experiment on hydrogen tank explosion was performed. In addition, the CFD numerical model was verified using the experimental results, and the damaging effect due to pressure propagation during hydrogen tank explosions in underground parking lots and road tunnels was analyzed using numerical analysis. From the experiment results, the hydrogen tank exploded at about 80 Mpa, a maximum incident pressure is generated 267 kPa at a distance of 1.9 m. As a result of numerical analysis based on the experimental results, the limit distance that can cause serious injury due to the explosion of a hydrogen tank in a road tunnel or underground parking lot was analyzed up to about 20 m from the point of explosion.