Characteristics and Safety for Open-Jet Flame of High-Pressurized Hydrogen

Abstract

The utilization of hydrogen for energy use is attractive since the exhaust gas is H₂O alone and will spread widely, when renewable energies and CO₂ reduction technologies are combined with the hydrogen-oxygen energy chain. In order to promote the widespread use of fuel cell vehicles, supply stations of high pressure hydrogen should be constructed in a city area, based on the safety regulations such as maximum storage amount, layout, material, safety distance, or protection wall. For the purpose, fundamental data for the open-jet hydrogen flame of high-pressurized hydrogen up to 80MPa have been accumulated. In this report, the scale of diffusion flame, flame stabilization, and radiation from flame are discussed. Furthermore, when the blown-down cloud of high pressure hydrogen was ignited at several tens milliseconds delay, the flame propagated at a high speed over 400m/s through the hydrogen-air mixture with a strong turbulence. Moreover, the outline of risk assessment and safety countermeasures for hydrogen supply station is introduced.