Numerical simulations of a hydrogen release in the vicinity of a cubical building

Computational Fluid Dynamics techniques were employed to perform an impact assessment of a hydrogen release in the vicinity of a building and to study the interactions between a hydrogen plume released in the vicinity of cubical buildings and the near-field flow structure. The impact of hydrogen's buoyancy on the near-field flow structure and dispersion characteristics as compared to plumes driven solely by momentum was estimated. Additionally, the effects of neighboring buildings on the flow field and dispersion characteristics of hydrogen were also estimated. The results of the various analyses showed that hydrogen, when released under several atmospheric stratifications, has a considerably greater impact potential in compared to methane. It was also shown that hydrogen's buoyancy strongly affects the flow structure about a cubical building and thus dispersion characteristics. Although the effects of buoyancy on the flow structure resemble those of neutral plumes driven solely by momentum, the effects on the dispersion characteristics were clearly different. Finally, it was shown that the addition of adjacent buildings to a single-building facility will markedly alter the flow field about the building and thus the dispersion pattern of hydrogen. Downwash algorithms, such as those employed by commonly used dispersion models, need to be revised as to incorporate the effects of buoyancy and adjacent buildings. CFD techniques were proven suitable for simulating the complex interactions associated with hydrogen dispersion in urban scenarios. Additionally the usefulness of CFD simulations as part of safe building/facility design protocols was showcased by the enhanced description of impacts associated with hydrogen dispersion.