Synergistic jet engines for cleaner aviation
An EU-funded project has developed new engine design concepts with the potential to radically improve aircraft efficiency, reduce greenhouse gas emissions, increase sustainability and boost European industry competitiveness. These new designs aim to maximise synergies between various existing and novel engine technologies.
© Jag_cz #187208107, 2019 source: stock.adobe.com
Although current aero engines are highly developed, only about 40 % of the energy stored chemically in the fuel is used to power the aircraft. The rest is lost due to inefficiencies that means there is still room for radical improvements in fuel efficiency, which is matched by a demand to reduce emissions.
This has been highlighted by the Advisory Council for Aviation Research and Innovation in Europe (ACARE) which has set ambitious emissions targets in line with EU goals. ACARE has called for a 75 % reduction in CO2 emissions and a 90 % reduction in nitrogen oxides (NOx) emissions per passenger kilometre by 2050. These targets can only be achieved by improving engines, airframes, engine-airframe integration and air-traffic management.
To address this challenge, the EU-funded ULTIMATE project has developed radical new propulsion concepts that should help the aviation industry meet the targets. The partners have studied how different technologies could be combined to work together in synergy to improve efficiency and reduce emissions. If fully implemented, the engine concepts proposed by the ULTIMATE project could save 3 billion tonnes of CO2 emissions over the first 20 years after 2050.
The technologies combined in our new engine systems benefit one another, says project lead Tomas Grönstedt of Chalmers University of Technology in Sweden. This is the first time that the synergies between different radical engine technologies have been explored systematically to create low-emission propulsion engines.
Efficient jet propulsion
From a long list of possible aero-engine technologies, the ULTIMATE team has focused on those that will work most effectively together. The researchers have explored concepts with the potential to make step-change improvements in efficiency and emissions.
Next, the project team made system models that put candidate technologies with the greatest potential synergies together. Based on efficiency estimates for each component, they were able to accurately predict how new and existing engine system components would interact and optimise the engine performance cycles.
These new jet engines could dramatically improve aircraft efficiency and reduce emissions. They may also be used in novel aircraft designs, like blended wing bodies, with new fuels such as biofuels, hydrogen or methane, and together with turboelectric systems.
The industry still needs to mature these propulsion-system concepts and propose roadmaps for testing and production of engines embodying the ULTIMATE concepts. This cutting-edge technology development could boost the long-term competitiveness of Europes aviation industry and provide high-paid jobs, says Grönstedt.
Radical engine concepts work
Grönstedt emphasises the importance of the project outcomes: Radical improvements to aviation will only happen if the engineering community believes they are possible. Engineers dont like to introduce unnecessary technical risk and they need to know that improvements can be made economically. The ULTIMATE project has indicated that such engines are feasible, which will help to increase confidence in these radical concepts.
The project team displayed engine mock-ups at the UKs 2018 Farnborough International Airshow to demonstrate how these concepts could become a reality. The ideas have already received international media attention and been featured in a two-page environmental special in Flight International magazine.
This attention has helped to disseminate the project to a wider audience. Several PhD and Masters degree students have been trained under the ULTIMATE project umbrella and over 40 research publications have already been written. Roadmaps are currently being developed to provide a framework showing how the technologies could be developed into products and brought to the market; they will also outline ways forward for further research on European propulsion and aviation.