关键词: 氢, 数值模拟, 气液两相流, 可燃氢气云团扩散, 加氢站安全, 氢浓度预测

Abstract:

With the widespread application of hydrogen as a clean energy source, its safety issues are increasingly valued. Due to the dangerous characteristics of hydrogen such as low density, high dispersibility and wide combustible range, it is easy to form a large flammable cloud after leakage, which may cause fire or explosion in case of ignition source, posing a serious threat to public safety. Conducting safety research on the diffusion pattern of liquid hydrogen leakage can prevent and reduce hydrogen leakage accidents, protecting people's lives and property. This study employs computational fluid dynamics (CFD) software Fluent, combined with the Lee model and the volume of fluid (VOF) model, to simulate the leakage and vaporization process of liquid hydrogen. The study finds that an increase in wind speed extends the downwind diffusion distance while reducing the vertical height. Based on the diffusion pattern of combustible hydrogen clouds and considering the limitations of hydrogen gas sensors, a new method is proposed to predict hydrogen concentration by monitoring environmental temperature changes using temperature sensors. By analyzing the mathematical relationship between temperature and hydrogen concentration during the initial leakage phase, a mathematical model is established to verify that the temperature sensors arranged on the 0.8 m height plane can quickly respond to leaks and improve the safety management level of hydrogen refueling stations.

Key words: hydrogen, numerical simulation, gas-liquid flow, combustible hydrogen cloud diffusion, hydrogen refueling station safety, hydrogen concentration prediction