Numerical Simulation of Hydrogen Dispersion and Explosion in Closed Parking Garage with or Without the Structure of Crossbeam

Abstract:

This study utilized the FLACS software to evaluate the dispersion and explosion characteristics of hydrogen released through thermally activated pressure relief devices （TPRDs） when parking a hydrogen fuel cell vehicle （HFCV） in an enclosed parking facility. The research investigated the effects of crossbeams on hydrogen dispersion patterns， concentration distribution， and post-explosion overpressure. Results indicate that crossbeams impede lateral hydrogen diffusion along the ceiling， resulting in concentration increases of up to 73% near the leak point and decreases of up to 25% in more distant areas. While crossbeams reduce the total combustible volume within the parking facility， they lead to higher overall concentrations of combustible gases. Moreover， the presence of crossbeams results in a 23% increase in maximum post-explosion pressure within the parking facility， thereby heightening the potential for casualties and injuries during an explosion event.