|The fuel cell system on the Airbus A320 ATRA research aircraft was built by DLR. Right: Airbus Project Leader Jens Dietrich Kurre. Click to enlarge. Credit: Airbus Deutschland.|
The Institute for Technical Thermodynamics of the German Aerospace Center (Institut für Technische Thermodynamik des Deutschen Zentrums für Luft- und Raumfahrt, DLR), together with its partner Airbus, has equipped and flown its Airbus A320 ATRA (Advanced Technology Research Aircraft) testing a 20 kW Michelin PEM hydrogen fuel cell system for use in auxiliary power applications.
In July 2007, the first flight experiments were made in which the function of the fuel cells under flight conditions were tested and demonstrated. The system worked consistently below 3G, with enough in store for a standby system. Since February 2008 the same fuel cell system has been used to power a hydraulic circuit pump, with the necessary power to steer the aircraft.
Fuel cell technology provides an improvement in fuel efficiency for aircraft, minimizing environmental pollution and increasing comfort and safety. DLR has, because of its long-term research experience, developed a high degree of expertise in all aspects of fuel cell technology from theory, to system development, commissioning and integration.—Prof. Johann-Dietrich Wörner, Chairman of DLR Executive Board
The fuel cell project is part of The German Federal Ministry of Economics and Technology (Bundesministerium für Wirtschaft und Technologie, BMWi) funded project ELBASYS (electrical base system), which is intended to support the introduction of technologies to minimize emissions and to increase passenger comfort.
|System performance at underpressure. Click to enlarge.|
PEM fuel cells face a number of issues in commercial aviation applications, aside from the challenges of building an infrastructure for the supply of oxygen and hydrogen fuel, and developing approved flight test measuring instruments for the fuel cell system.
Harsh environmental (temperature and pressure) conditions are one example. PEM fuel cells can experience major performance degradation with ambient pressure variation. Membrane humidification is hindered due to shifting boiling temperatures at different altitudes. Acceleration, inclination and vibration are others.
|Drawing of the fuel-cell Antares DLR-H2. Click to enlarge.|
DLR is also working with Lange Aviation GmbH on the Antares DLR-H2, a flying test-bed for further work on fuel cell technology for aviation. Lange Aviation in Zweibrücken develops and builds the aircraft, while the DLR Institute for Technical Thermo- dynamics prepares the fuel-cell system, which is used as the primary propulsive system. The power train consists of power electronics, motor and propeller.
The research aircraft and its propulsion system is substantially based upon the Antares 20E, a self-launching powered sailplane, which already has been in series production for some years. Two additional external pods, which house fuel cells and fuel tanks, are added underneath the specially strengthened wing. In the future, the performance of the aircraft may be increased substantially by using up to four external pods, or by using fuel cells of an improved design.
The cooperation between DLR and Lange Aviation has been constructed as a long term partnership, so that the research aircraft is available to DLR until 2017. DLR provides the power source and defines and evaluates the research assignments, while Lange Aviation designs and builds the research aircraft.