停车场内氢能客车氢泄漏爆炸事故及风险分析

Study on Hydrogen Leakage-Explosion and Risk of Hydrogen Bus in Station

近年来,氢燃料电池汽车发展迅速。相较于氢燃料电池小汽车,氢能客车的尺寸大、储氢量大,存在的安全风险更大,研究停车场内氢能客车的氢泄漏爆炸事故及风险具有重要意义。采用FLACS软件预测停车场内的氢能客车关键部件失效后不同泄漏工况下的氢气云团的扩散过程,根据泄漏后氢气云团的含量分布特性,研究在不同点火位置下诱发氢气云爆炸事故后的爆炸超压特性;分析事故的影响范围,量化爆炸事故后果,提出爆炸风险防控建议;结合预测的事故发生概率对停车场内的氢能客车开展氢泄漏的风险分析,提出了一种氢能客车氢泄漏爆炸事故及风险分析方法。研究结果表明,环境风和停车场的规划布局都会影响泄漏后的氢扩散行为,当环境风向与停车场顶棚长度方向垂直时最有利于氢气的扩散,在大型客车停车场内氢能客车发生氢气泄漏后的扩散速度快,氢含量迅速下降,点火引发氢气云爆炸产生的爆炸冲击波威力较小,在最严重的泄漏场景下最大爆炸超压约为12.38 kPa。可在氢能客车TPRD装置附近以及停车位中间偏后对应的顶棚位置上安装灵敏度高的氢传感器,以提高实时监测氢气泄漏的灵敏度。停车场内氢泄漏后诱发氢气云爆炸事故的风险近似为3.64×10−^(7)次/年,低于风险可接受水平,该客车停车场符合安全性要求。研究结果为氢能客车与停车场内氢浓度传感器的布局以及停车场的规划建设提出了合理建议。

Hydrogen vehicles have developed rapidly in recent years.Compared with hydrogen cars,hydrogen buses have greater safety risks due to their large sizes and large passenger capacity,so it’s of great significance to study the hydrogen leakage-explosion accidents and risks of hydrogen buses in station.The study predicted the dispersion of hydrogen under different leakage conditions after the failure of critical components of hydrogen bus with software FLACS.It studied the overpressure characteristics of the explosion after the explosion induced by the vapor cloud under different ignition locations according to the volume concentration distribution characteristics of hydrogen.And it analyzed the impact range of the accident,quantified the consequences of the explosion accident,and put forward the explosion risk prevention and control suggestions.Based on the risk analysis of hydrogen leakage in the parking lot,it put forward a risk analysis method of hydrogen leakage and explosions.The results show that the environmental wind and the planning layout of the station will affect the hydrogen dispersion after leakage.When the environmental wind direction is perpendicular to the length of the parking lot ceiling,it is most conducive to the dispersion of hydrogen;the dispersed velocity after the hydrogen leakage in the large sides station is fast;the hydrogen volume concentration decreases rapidly;the overpressure generated by ignition induced gas cloud explosion is less powerful;the maximum overpressure in the most severe leakage scenario is approximately 12.38 kPa.The high sensitivity hydrogen sensors can be installed near the TPRD device of hydrogen bus and at the corresponding ceiling position in the middle of the parking space to improve the sensitivity of real-time monitoring of hydrogen leakage.The risk of gas cloud explosion accident after hydrogen leakage in the parking lot is approximately 3.64×10^(-7) times per year,which is lower than the risk acceptable level,indicating the bus parking lot meets the safety requirements.The research results provides reasonable suggestions for the layout of hydrogen sensors in hydrogen buses and station,as well as the planning and construction of station.