Characteristics of Hydrogen Leakage Sound from a Fuel Cell Vehicle by Hearing (Second Report)

Abstract

Fuel-cell vehicles are designed so that hydrogen flow is automatically stopped after detection of a hydrogen leak or detection of a crash. However, to examine the method for performing safe rescue using human auditory sense in the event of a continuous hydrogen leak, we investigated the relationships between the detectable flow rate of hydrogen in a traffic-noise environment at a downtown crossing and the vehicle type, hydrogen leak direction, shape of the leaking part, audible distance, and ages of subjects. Tests were conducted by reproducing the recorded traffic noise while helium leaks from a hydrogen vehicle in an anechoic room. As a result, we found that hydrogen leakage sound can be recognized in a traffic-noise environment, that the leak from a which has higher vehicle height is heard more easily than that from a lower one, that leaks are easier to detect with a smaller cross-section of the leaking part and closer to the vehicle, and that there is almost no dependency on age.