Hydrogen fuel cell explosion risk assessment

The Challenge

Hydrogen fuel cells are a promising technology for small to medium sized power, particularly for road and rail freight. However, hydrogen has a wide flammability range and its deflagration-to-detonation distance, the point at which a low-grade explosion becomes a destructive supersonic detonation, is poorly characterized. The customer needed to know if the containment vessel for their fuel cell design would withstand such an explosion.

The Solution

Element Digital Engineering addressed this challenge in three parts, drawing on our considerable experience of explosion risk assessments in the offshore gas industry. Firstly, chemical equilibrium modeling was used to establish the peak deflagration and detonation pressures for a range of internal leak and ignition scenarios. These pressures were then applied to a model of the vessel to determine whether it would fail. Finally, a missile fragment energy assessment method from the nuclear energy was used to establish whether these fragments would pierce the outer containment.

The Result

It was established that even if detonation conditions were assumed, which were unlikely in the length scales of the vessel, the failure probability was acceptably low. The customer has been able to progress with development of their fuel cell.