Rolls Royce engaged in the development of a technology of hydrogen combustion enginescapable of powering a range of devices, in the segment of single-aisle aircraft from 2030.
In partnership with the airline easyJet and in collaboration with Loughborough University in the United Kingdom and the German aerospace center Deutsches Zentrum für Luft-und Raumfahrt (DLR), Rolls-Royce has demonstrated engine technology that marks a new milestone in path to using hydrogen as an aeronautical fuel.
Tests on a complete annular combustion chamber of a Pearl 700 engine at the DLR in Cologne, running 100% on hydrogen, were successful. They proved that fuel can be burned under conditions corresponding to maximum takeoff thrust.
The key to this success lies in the design of new fuel spray nozzles to control the hydrogen combustion process. This required significant technical challenges, because hydrogen burns much faster and at a higher temperature than kerosene. The new nozzles made it possible to control the position of the flame using a new system that gradually mixes air with hydrogen to manage fuel reactivity. Rolls-Royce was able to confirm that combustion chamber operability and emissions met expectations.
The individual nozzles were first tested at intermediate pressure at the recently upgraded Loughborough testing facilities and at DLR Cologne, before final testing of the combustion chamber at full pressure took place at DLR Cologne .
Last year, easyJet and Rolls-Royce also achieved a world first by successfully operating a green hydrogen engine, an AE2100, at Boscombe Down, UK.
These recent trials mean that the combustion element of the hydrogen program is now well understood, while work continues on the engine’s fuel delivery systems and the integration of these systems into an engine.
Grazia Vittadini, head of technology at Rolls-Royce, said: “This is an impressive achievement in a very short period of time. Controlling the combustion process is one of the main technological challenges that the industry must overcome to make hydrogen a true aeronautical fuel of the future. We succeeded and it makes us want to continue moving forward. I would like to thank easyJet, Loughborough University and the DLR for their dedication and support in getting us to this milestone”.
Johan Lundgren, CEO of easyJet, recalled: “We believe that hydrogen is the future of short-haul aviation and the success of this test and the progress made demonstrate that we are getting closer and closer. We remain optimistic that hydrogen will play a vital role in helping us achieve the ambitious goals we have set in our zero emissions roadmap.“.