Safe use of hydrogen energy: review on hydrogen self- ignition and generated hydrogen jet fire

Abstract

In the fight against climate change, hydrogen is seen as a promising sustainable energy alternative to fossil fuels. However, its wider adoption has raised safety issues, particularly regarding spontaneous combustion without an external spark. To ensure safe and sustainable hydrogen use, researchers have developed a thorough research approach targeting hydrogen's potential for spontaneous combustion. Progress has been made in understanding this phenomenon within transparent extension tubes, examining various factors like tube dimensions, curvature, shape, and rupture disc properties. These studies have revealed consistent trends. Simulations have helped explain how hydrogen auto-ignites, often starting at the tube wall, especially in high-pressure situations where it interacts with hot air and expands cold fuel. Researchers have also created mathematical models related to ignition dynamics. Yet, there's limited experimental data on hydrogen jet self-ignition in open spaces. Some simulations suggest that high-pressure hydrogen can ignite spontaneously even without a confinement, but the ignition event is so brief that it's difficult to capture experimentally. Moreover, scholars are creating more accurate empirical formulas based on extensive experimental statistics that connect internal tube ignition to external jet flames. The accuracy of these empirical estimates improves as more experimental data becomes available.