Dispersion modelling and analysis of hydrogen fuel gas released in an enclosed area: A CFD-based approach

The use of hydrogen gas as a fuel to be burned or to be spent in a hydrogen fuel cell vehicle is increasing. While hydrogen is a renewable and clean energy career, the safety aspects associated with it is still a key issue. Hydrogen has a wide flammability range and needs less energy to be ignited, compared to other common fuels. Experiments on hydrogen safety are not an economic and safe approach; hydrogen is a very dangerous substance, and expensive to test in a safe environment. Use of Computational Fluid Dynamics (CFDs) is an alternative method to predict the behaviour of hydrogen gas after an accidental release. Providing the concentration profile for the area of concern, and the ability to investigate different parameters such as ventilation, obstacles' configurations and ignition sources are the advantages of using CFDs codes for the safe design of hydrogen stations and hydrogen fuel cell vehicles. In the current study, a CFD based approach is proposed to evaluate the dispersion behaviour of hydrogen gas after a release from a hydrogen fuel cell car in an enclosed area. The fuel concentration profile in the compartment is produced, considering different ventilation conditions. Mitigation measures are also applied to improve the ventilation condition and decrease the fuel concentration below the flammable level. The proposed approach is useful for better design of safety measures to prevent consequent accidents or minimise the harmful impacts during an accident.