김부승  서국진  유은결  최영보

Vol. 39,  No. 4, pp. 48-55, Aug.  2024
10.14341/JKOSOS.2024.39.4.48

hydrogen refueling stations machinery room hydrogen leaks explosion risk assessment Computational fluid dynamics FLACS equivalent ratio ignition timing

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South Korea is actively pursuing leadership in hydrogen energy. Ensuring the safety of hydrogen refueling stations emerges as a pivotal task for the rapid evolution of South Korea into a hydrogen-based society. Quantitative risk assessments (QRAs) have been rigorously undertaken at these facilities to mitigate the risk of severe accidents. However, conventional QRA methods, which rely on two-dimensional representations of open spaces, encounter significant constraints in the analysis of indoor explosion scenarios. Furthermore, numerous computational fluid dynamics (CFD)-based QRAs have failed to thoroughly incorporate critical factors such as ignition timing and hydrogen concentration, which decisively influence explosion dynamics. This study aimed to overcome these shortcomings by performing leak simulations within a threedimensional framework using FLACS CFD software inside the machinery room of a hydrogen refueling station equipped with a high-pressure storage system. Explosion simulations were subsequently performed at locations where variables V Q9 and V ΔFL attained their maximum values within an equivalent stoichiometric cloud. These simulations were performed at seven distinct points with different equivalent ratios to assess the resultant overpressure and its impact on adjacent infrastructure. The simulation findings indicated that explosions at maximum VQ9 values yielded peak overpressures that were 1.5–2.7 times those observed at maximum V ΔFL values; further, the effects on nearby equipment varied significantly, exceeding a tenfold difference in some instances. This study also explored strategies to mitigate and prevent the impacts of hydrogen leaks and related explosive events.