Computational study of a high-pressure hydrogen storage tank explosion at different heights from the ground

Abstract

A computational study was carried out to investigate the explosion of a 35-MPa, 72.4-L high-pressure hydrogen storage tank at different heights from the ground. The numerical simulations were carried out using OpenFOAM computational fluid dynamics code. The numerical simulation incorporates a k−ω shear stress transport turbulence model and an eddy dissipation concept combustion model with a one-step finite rate reaction. The prediction performance of the numerical approach was validated based on experimental results obtained from previous studies. The hydrogen tank explosion was investigated at different heights (h; 0.0, 0.2, 0.5, 0.8, and 1.0 m) from the ground and at h = 0.2 m from the ground with θ = 65°). The numerical predictions showed that tank height and position significantly affect the blast overpressure strength and propagation. The reflected pressure magnitude increased as the tank height decreased with respect to ground level. At farther distances, the explosion scenario of h = 0.2 m and θ = 65° showed stronger maximum overpressure and impulse hazards than the other height settings. The difference in maximum overpressure magnitude between the different explosion scenarios was insignificant at 4 m from the tank. Hydrogen gas auto-ignites closer to the ground, due to the compression effect attributed to the Mach stem phenomenon. Our results showed that blast effects in the radial direction are more hazardous than those in the axial direction.