Safety evaluation on devices of high-pressure hydrogen refueling stations

Abstract

Hydrogen refuelling stations are established in various places nowadays. With the development on the hydrogen refuelling under higher pressures, the risk of hydrogen leakage on the devices, specifically the compressor and the dispenser, draws increasing concerns for these stations. In this paper, different cases of hydrogen leakage and combustion are evaluated for these devices with respect to various conditions, based the prototypes designed for a high-pressure hydrogen refuelling station in China. The results show that the limited hydrogen flow in the compressor ensures that no serious accident will occur after leakage. As for the dispenser, the cases for internal leakage on the main tube and the external leakage on the nozzle hose are studied and compared. According to the results, the harmful and lethal distances are obtained. Also, the effect of wind speed on the gas diffusion field and the temperature field are quantified by the simulation. It can be stated that the severity of ignition will increase with consideration of the wind. The results can be beneficial to the timely detection of the possible hydrogen leakage of the devices, and to the optimized layouts for the design of stations.