风速对城市公路隧道氢运输车辆泄漏扩散的影响

The Effect of Wind Speed on the Leakage and Diffusion of Hydrogen Transport Vehicles in Urban Highway Tunnels

为了解不同风速下公路隧道内氢运输车辆泄漏后气体的扩散规律,运用PyroSim软件研究城市公路隧道内不同风速下氢运输车辆泄漏后氢气浓度的分布规律。结果表明:无风情况下,氢气云受动量和浮力作用迅速向两端隧道口扩散,整条隧道顶部在40s内到达爆炸下限,并维持较长时间;有风情况下,氢气沿泄漏口下风向扩散,随着风速增大,氢气云高度下降,隧道顶部氢气浓度迅速降低,中下部氢气浓度呈现先增大再降低的趋势。在隧道内发生氢运输车辆泄漏后应急通风的风速应控制在10m/s以上。研究结论可为公路隧道内氢运输车辆泄漏事故应急救援、隧道通风系统优化设计提供理论指导。

In order to understand the diffusion law of gas leakage in hydrogen transport vehicles in highway tunnels under different wind speeds,the PyroSim software was used to study the distribution law of hydrogen concentration after hydrogen transportation vehicle leakage in urban highway tunnels at different wind speeds.The results show that:under the windless condition,hydrogen clouds rapidly diffuse towards the tunnel openings at both ends due to momentum and buoyancy effects and reaches the explosion limit at the top of the tunnel in 40s,and maintains for a long time;In windy conditions,hydrogen spreads along the downwind of the leakage outlet.With the increase of wind speed,the height of the hydrogen cloud decreases,the concentration of hydrogen at the top of the tunnel decreases rapidly,and the concentration of hydrogen in the middle and lower parts increases first and then decreases.The wind speed of emergency ventilation after the leakage of hydrogen transport vehicles in the tunnel should be controlled above 10m/s.The conclusions can provide theoretical guidance for the emergency rescue of hydrogen transport vehicle leakage in highway tunnels and the optimized design of tunnel ventilation system.