Modeling the Consequences of BLEVEs Involving Liquid Hydrogen Components

The significant advances made in hydrogen storage and transport techniques, along with the necessity to satisfy the market needs, led to a notable increase in the use of liquid hydrogen (LH2). On the one hand, LH2 is convenient in terms of storage capacity and energy content per unit volume. On the other hand, it poses relevant safety issues that must be considered to ensure its reliable and safe utilization. From a safety standpoint, one of the most critical scenarios is the fire exposure of cryogenic tanks. When it occurs, pressure buildup manifests in the component due to the formation of boil-off gas. As a result, the cryogenic equipment could fail catastrophically, potentially generating a boiling liquid expanding vapor explosion (BLEVE). The hazardous consequences of this phenomenon include the blast wave, the projection of fragments, and the fireball. This work aims to provide a prediction of the consequences of an LH2 BLEVE arising from cryogenic components involved in LH2 storage and transfer operations, such as tanks and hoses. Analytical models able to assess blast wave and fireball effects were implemented in the engineering tool BLEXCOM. A new approach is proposed to accurately determine the LH2 BLEVE blast overpressure and impulse. The experiments conducted in the Norwegian research project SH2IFT are considered as case study and exploited for validation purposes. This research is expected to yield innovative insights into the contribution of hydrogen combustion to the effects of the BLEVE consequences. Ultimately, the proposed model could be used during the design phase of inherently safer LH2 equipment.