Evolution of Explosion-Venting Flow Field and Hazard Induced by a Vented Hydrogen Explosion in a 45 m³ Container

Hydrogen, as an emerging energy source, is extensively utilized in industrial production. Owing to its high reactivity, hydrogen presents an explosion risk during its utilization, storage, and production, potentially resulting in significant harm to personnel and equipment. To elucidate the dynamic characteristics of external explosions induced by different ignition positions in hydrogen-related plants, this study developed a 45 m3 hydrogen explosion-venting model using computational fluid dynamics technology. A fascinating numerical analysis was conducted on the flow field, distribution characteristics, and disaster evolution of external explosions induced by inner hydrogen explosions. The results show that when the ignition was far away from the vent, the combustion rate and speed of the outdoor jet flame significantly increased, thus comprehensively enhancing the trigger energy of the external explosion. A new overpressure peak structure formed by the superposition of the rupture wave and the external explosion wave was observed. Compared with the central ignition, the new shock wave intensity caused by back ignition was the highest, which could increase the overpressure level by 57% and lead to new overpressure hazards in the far field. In the case of back ignition, the high-temperature area was twice the length of the room, while the high-temperature area was the smallest when the front ignition. The ignition location did not significantly affect the position of the maximum wind velocity. However, back ignition could result in wind velocities of up to 18 times that of a hurricane wind. The research results are expected to provide a reference for explosion risk control, explosion-venting hazard mitigation, and prevention of simple industrial plants.