Effect of Tunnel Ventilation on Hydrogen Dispersion From Leaks in Hydrogen Fuel Cell Trucks

ABSTRACT The widespread adoption of hydrogen fuel cell trucks (HFCTs) depends on addressing hydrogen safety concerns, particularly in confined spaces like tunnels, where effective ventilation is crucial to prevent accumulation during leaks. This study uses a computational fluid dynamics (CFD) model to simulate hydrogen dispersion and evaluates key ventilation factors—velocity, area, placement, and spacing. An orthogonal sensitivity analysis identifies vent area as the dominant parameter, leading to the optimal ventilation strategy. The results confirm that increasing ventilation velocity and vent cross‐sectional area significantly improve hydrogen exhaust efficiency. Specifically, increasing ventilation velocity from 5 to 20 m/s reduced the flammable cloud volume by 55.35%, while expanding the vent area from 1 to 4 m 2 reduced it by 49.62%. The vent cross‐sectional area was identified as the most influential parameter. Furthermore, top‐mounted vent placement proved more effective than sidewall configurations, and a 50 m longitudinal spacing outperformed 100 m in minimizing the hydrogen cloud. Consequently, the optimal ventilation configuration is a system with a velocity of 20 m/s, top‐mounted vents, a cross‐sectional area of 4 m 2 , and 50 m spacing.