In current aircraft technology there is the hydraulic system for operating inter alia the flight control system. This hydraulic system is divided into three different circuits (green circuit, yellow circuit, blue circuit). Under high loads in these circuits the maximum allowable temperature of the hydraulic fluid (e.g. Skydrol) of 90° C. can be reached, which causes high stress in the individual components (pumps, conduits, and seals). This reduces the reliability of these components.
A fuel cell is an electrochemical reactor, which produces electric and thermal energy from the reactive gases hydrogen and oxygen. The electric energy is conducted from the cell e.g. as direct current and conditioned accordingly for further use. The thermal energy, which is produced, has to be removed through a cooling circuit, so that the fuel cell does not overheat during operation, and does not get damaged.