摘要 |
An arrangement for high temperature fuel cell system for substantially reducing the amount of purge gas in an emergency shut-down situation. The arrangement includes a known volume for containing a pneumatic actuation pressure, the known volume including at least one discharge route for designed discharge rate, at least one pressure source providing pressure capable of performing the pneumatic actuation, at least one purge gas source having a gas overpressure capable of displacing residual reactants in the fuel cell system. Purge gas is discharged through the discharge route causing pressure decline in the known volume, accomplishing a designed time delay in state change of at least one pneumatically actuated valve, to reduce or close down completely emergency shutdown actuated flow of the purge gas into the fuel cell system piping after the designed time delay. |