(Posted 26th September 2023)
Rolls-Royce announced a further key milestone, a world industry first, has been achieved in its hydrogen
research project.
Both Rolls-Royce and its partner easyJet are committed to being at
the forefront of the development of hydrogen combustion engine
technology capable of powering a range of aircraft, including those
in the narrow-body market segment, from the mid-2030s onwards.
Now, working with Loughborough University in the UK and the
German Aerospace Centre Deutsches Zentrum für Luft-und
Raumfahrt (DLR), Rolls-Royce has proven a critical engine
technology that marks another significant step in the journey to
enabling hydrogen as an aviation fuel.
Tests on a full annular combustor of a Pearl 700 engine at DLR in
Cologne running on 100% hydrogen have proven the fuel can be
combusted at conditions that represent maximum take-off thrust.
Key to that achievement has been the successful design of advanced
fuel spray nozzles to control the combustion process. This involved
overcoming significant engineering challenges as hydrogen burns
far hotter and more rapidly than kerosene. The new nozzles were
able to control the flame position using a new system that
progressively mixes air with the hydrogen to manage the fuel’s
reactivity. Rolls-Royce is pleased to confirm that combustor
operability and emissions were both in line with expectations.
The individual nozzles were initially tested at intermediate pressure
at Loughborough’s recently upgraded test facilities and at DLR
Cologne before the final full-pressure combustor tests took place at
DLR Cologne.
Last year, easyJet and Rolls-Royce also set a world first by
successfully running a modern aero engine, an AE2100, on green
hydrogen at Boscombe Down, UK.
These recent tests mean the combustion element of the hydrogen
programme is now well understood, while work continues on systems
to deliver the fuel to the engine and integrate those systems with an
engine.
Grazia Vittadini, Chief Technology Rolls-Royce, said:
“This is an incredible achievement in a short space of time. 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, said:
“We believe hydrogen is the future of short-haul aviation and the
success of this test and progress being made demonstrates that this is
becoming ever closer. We remain optimistic that it will play a critical
role in helping us achieve the ambitious goals we set out in our net zero
roadmap.”
Professor Dan Parsons, Pro Vice-Chancellor for Research and
Innovation, Loughborough University, said:
“In conjunction with its partners, the National Centre for Combustion
and Aerothermal Technology (NCCAT) at Loughborough is delighted to
have supported the landmark testing and development of advanced
aerospace fuel spray nozzles utilising hydrogen fuel. This is a major
advance towards net zero aviation.”
Markus Fischer, Divisional Board Member Aeronautics of DLR, said:
“This is an outstanding success story and we are more than happy to
have contributed our hydrogen testing capabilities. It was very exciting
supporting this technology journey and seeing the burner technology
mature in various rigs at our Institute of Propulsion Technology. This
underlines again DLR’s capabilities in complex applied research and the
achievement, at such a high pace, was supported by our experience in
real-scale testing of ground-based gas turbines.”
The technologies tested at Loughborough and DLR will now be incorporated into the learning from the Boscombe Down tests as Rolls- Royce and easyJet prepare for the next stage of testing – a full gas hydrogen ground test on a Pearl engine.
That will in turn lead to a full ground test on a Pearl engine using liquid
hydrogen – both easyJet and Rolls-Royce have a shared ambition to then
take the technology to flight.
Rolls-Royce receives support for hydrogen research through the UK’s
Aerospace Technology Institute HyEST programme, Germany’s LUFO 6
WOTAN programme, and the European Union’s Clean Aviation CAVENDISH
programme. Loughborough is a partner in HyEST and CAVENDISH. DLR is a
partner in WOTAN and CAVENDISH. easyJet has provided investment to
support the development of hydrogen combustion engine technology for
narrow-body aircraft.
