In the experiment of 13. September 1996 the hydrogen gas cushion which had been created above the liquid hydrogen in the tank was released. This process is comparable to the venting of an express cooking pot. The venting of the gas lets the pressure drop, more hydrogen evaporates, and the remaining liquid is further cooled. This process is monitored by means of temperature sensors in the hydrogen tank to gain data on the temperature stratification and other aspects of the thermal behavior.
Further measurements cover the strains and other mechanical properties.
The experiments are not yet finished, so that no final statements can be made now. The release experiments aims as simulating the later emptying of the tank after transport. The tank designers want to keep the hydrogen losses in transport as low as possible. The thermal insulation shall be so good that over a transport time of e. g. 25 days the pressure rise is so low that the safety valves do not react.