Consequence Analysis of Liquid Hydrogen Leakage from Storage Tanks at Urban Hydrogen Refueling Stations: A Case Study

Hydrogen energy is considered a crucial clean energy carrier for replacing fossil fuels in the future. Liquid hydrogen (LH2), with its economic advantages and high purity, is central to the development of future hydrogen refueling stations (HRSs). However, leakage poses significant fire and explosion risks, challenging its safe industrial use. In this study, a numerical model of LH2 leakage at an HRS in Chongqing was established using Computational Fluid Dynamics (CFD) software. The diffusion law of a flammable gas cloud (FGC) was examined under the synergistic effect of the leakage direction, rate, and wind speed of an LH2 storage tank in an HRS. The phase transition of LH2 presents dual risks of combustion and frostbite owing to the spatial overlap between low-temperature areas and FGCs. The findings revealed that the equivalent stoichiometric gas cloud volume (Q9) reached 685 m3 in the case of crosswind leakage, with the superimposed effect of reflected waves from the LH2 transport vehicle resulting in a peak explosion overpressure of 0.61 bar. The low-temperature hazard area and the FGC (with a concentration of 30–75%) show significant spatial overlap. These research outcomes offer crucial theoretical underpinning for enhancing equipment layout optimization and safety protection strategies at HRSs.