Rolls-Royce, in collaboration with Loughborough University, has achieved a groundbreaking milestone in their pursuit of net-zero aviation with a world-first hydrogen combustion engine technology project. The initiative, supported by easyJet, is poised to lead the aviation industry in harnessing the power of green hydrogen.
On Monday, September 25, Rolls-Royce announced a significant achievement in partnership with Loughborough University, the National Centre for Combustion and Aerothermal Technology (NCCAT), and the German Aerospace Centre, Deutsches Zentrum für Luft-und Raumfahrt (DLR). Together, they have made significant progress in making hydrogen a viable aviation fuel.
In Cologne, at DLR's facilities, the project conducted tests on a full annular combustor of a Pearl 700 engine, running entirely on 100% hydrogen. The results demonstrated that hydrogen can be combusted under conditions simulating maximum take-off thrust. A pivotal part of this success was the design of advanced fuel spray nozzles that control the combustion process. This endeavor overcame substantial engineering challenges, as hydrogen burns much hotter and more rapidly than kerosene. The newly designed nozzles effectively managed the flame position by progressively mixing air with hydrogen to control the fuel's reactivity. Rolls-Royce confirmed that combustor operability and emissions were in line with expectations.
The initial testing of the individual nozzles took place at Loughborough's NCCAT test facilities at intermediate pressure levels. Subsequently, full-pressure combustor tests were carried out at DLR Cologne.
Notably, last year, easyJet and Rolls-Royce achieved a world-first by successfully operating a modern aero engine, the AE2100, using green hydrogen in Boscombe Down, UK.
With these recent breakthroughs, the combustion aspect of the hydrogen program is now well understood. The focus has shifted to developing systems for fuel delivery to the engine and integrating these systems seamlessly.
Grazia Vittadini, Chief Technology Officer at Rolls-Royce, expressed her enthusiasm, stating, "Controlling the combustion process is one of the key technology challenges the industry faces in making hydrogen a real aviation fuel of the future. We have achieved that, and it makes us eager to keep moving forward. I want to thank easyJet, Loughborough University, and DLR for their dedication and support to reach this milestone."
Johan Lundgren, CEO of easyJet, emphasized their belief in hydrogen as the future of short-haul aviation. The success of these tests demonstrates that this future is becoming increasingly attainable and aligns with their net-zero roadmap.
Professor Dan Parsons, Pro Vice-Chancellor for Research and Innovation at Loughborough University, celebrated the collaboration, stating, "In conjunction with its partners, Loughborough’s National Centre for Combustion and Aerothermal Technology is delighted to have supported the landmark testing and development of advanced aerospace fuel spray nozzles utilizing hydrogen fuel. This is a major advance towards net-zero aviation."
The technologies tested at Loughborough and DLR will now be integrated into the lessons learned from the Boscombe Down tests. This will enable Rolls-Royce and easyJet to progress to the next phase of testing: a full gas hydrogen ground test on a Pearl engine. The ultimate goal is to conduct a full ground test on a Pearl engine using liquid hydrogen, aligning with their shared ambition to bring this technology to flight.
Rolls-Royce's hydrogen research receives support from the UK's Aerospace Technology Institute HyEST program, Germany's LUFO 6 WOTAN program, and the European Union's Clean Aviation CAVENDISH program. Loughborough University is a partner in both HyEST and CAVENDISH, while DLR is a partner in WOTAN and CAVENDISH. easyJet has provided investment to advance hydrogen combustion engine technology for narrow-body aircraft. This partnership underscores the commitment to pioneering sustainable solutions for the aviation industry.