Heat transfer analysis of high-pressure hydrogen storage tanks subjected to localized fire

Safety performance of high-pressure hydrogen storage tanks under localized fire exposure has drawn extensive attention. During the localized fire, the tank would be degraded and even burst before pressure relief device (PRD) activates to release internal high-pressure gas. Therefore, a localized fire test method for the tanks is being developed. In this paper, a three-dimensional computational fluid dynamics model is developed to investigate the heat transfer characteristics of 70 MPa hydrogen composite tanks subjected to localized fire. The effects of different flame impingement areas on temperature and pressure rises of the tank are analyzed. Heat transfer performances of type 3 and type 4 tanks are compared. The results show that the temperature and pressure rises are not significant during the 600 s localized flame impingement process. When the flame impingement area of the tank is far from PRD, convective heat transfer of internal hydrogen may be more intense than heat conduction of tank wall in the longitudinal direction. In addition, the heat from localized fire can be transmitted faster in type 3 tanks than in type 4 tanks.