Research on hydrogen leakage and dispersion characteristics in indoor thermal stratification environment

The leakage of hydrogen in a room is a key issue of hydrogen safety, and ventilation plays an important role in hydrogen dispersion. The hydrogen leakage usually builds a thermal stratification environment due to the low temperature of liquid hydrogen or throttling effect. This study attempts to develop a fast-computational theoretical model of hydrogen dispersion motion in an indoor thermal stratification environment based on the classical buoyant jet model and to carry out an experimental to verify model. The research results show that the developed theoretical model can well predict the trajectory of slowly releasing hydrogen leakage. The motion trajectory of the hydrogen leak oscillates in the thermally stratified environment at a certain height, called as the “lock height”. The smaller the leak port in the uniform environment the larger the horizontal diffusion distance, and the smaller the leak port in the thermally stratified environment the higher the locking height. The research results are expected to predict the hydrogen leakage safety prediction problem and the formulation of related standards and help make ventilation strategies to ensure the hydrogen safety