Study on hydrogen dispersion in confined space with complex air supply and exhaust system

The safety issue involving unplanned H-2 leakage has retarded promotion of Hydrogen fuel cell vehicles (HFCVs). When an accidental leakage occurs in a relatively closed space, H-2 tends to accumulate. It is necessary to obtain a better understanding of the H-2 dispersion characteristics in a relatively closed space. Most studies focus on the dispersion features in a small garage, whereas few consider large underground garages with complex ventilation systems. Herein, H-2 released from a pressurized tank in a real large underground garage was investigated by a two-stage computational fluid dynamics (CFD) study. An isentropic expansion model with a real gas equation of state was employed in stage (1) to estimate the source strength which can be used as inlet boundary conditions for stage (2), the dispersion stage. The CFD models were validated against the experimental results. The concentration field and flammability envelope were focused. This study provides a feasible method for assessing the risks associated with HFCVs. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.