Evolution and Consequences of Fire Accidents Involving Gasoline Vehicles and Fuel Cell Vehicles in an Open Space

As fuel cell vehicles (FCVs) are increasingly being used, the safety of FCVs and their surroundings is a matter of growing concern. When FCVs are co-parked with gasoline vehicles, the single-vehicle accidents may extend and then result in fires involving multiple vehicles. To this end, the present study employs Computational Fluid Dynamics (CFD) to discuss the case of a fire involving one and two vehicles with different types of fuels. For single-vehicle accidents, the maximum hazard scenario for gasoline pool fires occurs when the fuel is fully burned, while the maximum hazard for hydrogen jet fires occurs at the beginning. Both types of single-vehicle fires activate the TPRD of the adjacent FCVs. The “gasoline-hydrogen” coupled fire exhibited the most substantial hazard range of thermal radiation, which is on average about 178% greater than the single-vehicle accident fire and is mainly concentrated on the right-front side of the gasoline vehicle. The “hydrogen–hydrogen” coupled accident is the fastest to reach its maximum, at 3.0 s, and the maximum hazard range is similar to that of gasoline pool fires. Overall, when hydrogen is present in a fire, it causes a slight decrease in flame height but an earlier onset of maximum hazard; when gasoline is present in a fire, it increases the flame duration and expands the area of low-hazard zone. Therefore, the potential consequences of an accident are most severe when gasoline vehicles and FCVs are parked in close proximity. To mitigate the risk of such incidents, it is imperative to implement additional safety measures or reduce fuel loadings.