Abstract: Fluent software is used to study the hydrogen leakage diffusion law and distribution of hydrogen in a hydrogen fuel cell bus under environmental wind. Taking a hydrogen fuel cell bus with a hydrogen storage capacity of 26 kg and a hydrogen storage pressure of 35 MPa as an example, a numerical model of hydrogen leakage diffusion in hydrogen fuel cell buses is established. The distribution of hydrogen concentration and combustible area (Volume fraction:4% ～ 75%) is comparatively analyzed under different window opening methods, environmental wind speeds and wind directions. The results show that the hydrogen concentration decreased by 3/4 when the windows are opened at the same time in the front and rear, but there is almost no effect on the volume of the combustible region. The hydrogen volume decreases by 13 m3 in the case of lateral incoming wind, but the hydrogen forms a larger size combustible hydrogen cloud outside the vehicle. When the ambient wind speed is higher, the concentration of hydrogen inside the car is lower, and the combustible range of hydrogen formed outside the car becomes smaller.

Key words: Hydrogen leakage; Hydrogen fuel cell bus; Environmental wind speed; Numerical simulation

摘要： 使用 Fluent 软件研究环境风下氢燃料电池公交车氢气泄漏扩散规律和分布情况。以储 氢量为 26 kg、储氢压力为 35 MPa 的氢燃料电池公交车为例，建立氢燃料电池公交车氢气泄 漏扩散数值模型，对比分析不同的开窗方式、环境风速、风向下的氢气浓度和可燃区域（体 积分数：4%～75%）分布情况。结果表明，前后同时开窗时，氢气浓度下降了 3/4，但是对可 燃区域体积几乎没有影响；侧向来风的情况下氢气体积减少 13 m 3，但是氢气在车外形成了较 大尺寸的可燃氢气云团；环境风速越大，车内氢气浓度越低，氢气在车外形成的可燃范围越 小。

关键词: 氢气泄露；氢燃料电池公交车；环境风速；数值模拟