Insights into Future Propulsion Technologies

Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Insights into Future Propulsion Technologies James Hunt Future Propulsion Lead Hamburg Aerospace Lecture Series, 23rd October 2025 https://doi.org/10.5281/zenodo.17729381 RAeS Hamburg in cooperation with the DGLR, VDI, ZAL & HAW invites you to a lecture DGLR / HAW Prof. Dr.-Ing. Dieter Scholz Tel.: 040 42875 8825 [email protected] RAeS Richard Sanderson Tel.: 04167 92012 [email protected] DGLR Bezirksgruppe Hamburg https://hamburg.dglr.de RAeS Hamburg Branch https://www.raes-hamburg.de VDI, Arbeitskreis L&R Hamburg https://www.vdi.de ZAL TechCenter https://www.zal.aero Hamburg Aerospace Lecture Series (AeroLectures): Jointly organized by DGLR, RAeS, ZAL, VDI and HAW Hamburg (aviation seminar). Information about current events is provided by means of an e-mail distribution list. Current lecture program, archived lecture documents from past events, entry in e-mail distribution list. All services via http://AeroLectures.de. Insights into Future Propulsion Technologies James Hunt, BSc Future Propulsion Lead, Advanced Manufacturing Research Centre (AMRC), University of Sheffield Date: Thursday, 23 October 2025, 18:00 Location: HAW Hamburg, Berliner Tor 5, Hörsaal 01.10 (in-person only!) James has over 25 years of experience in applied research in industry and academia, specializing in materials and manufacturing. After a decade in the UK steel industry, he joined the University of Sheffield to advance metals processing, including additive manufacturing and electron beam welding. As Future Propulsion Lead at AMRC, he works with industrial partners on zero-emission transport technologies. He authored a report on hydrogen storage for the ATI's FlyZero programme and collaborates with ATI’s Hydrogen Capability Network on hydrogen aircraft adoption. The aviation sector has set ambitious targets to achieve net zero flight by 2050, there are several legislative, operational and technological pathways that will contribute towards this. Some of the greatest challenges are faced in developing solutions that will directly reduce the emissions of the aircraft. This presentation will provide some insights into what technologies are being explored for future propulsion systems based on new and alternative fuels such as battery, hydrogen and sustainable aviation fuels (SAF). It will Aerospace Technology Institute (ATI), FlyZero, © ATI explain how the incumbent primes are adopting different approaches to decarbonisation, while emerging companies are seeking to carve out niches with their disruptive technologies and business models. Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) •Introduction to the AMRC •Setting the scene •Overview of propulsion systems •Technology developments •External factors •Summary 2 Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Introduction to the AMRC Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) What is the AMRC? 3 •Established in 2001 as a collaboration between industry & the University of Sheffield. •Helps manufacturers of any size to become more competitive by introducing advanced techniques, technologies and processes. •Specialises in carrying out world-leading research into advanced machining, manufacturing and materials, which is of practical use to industry. •Expertise in machining, automation, robotics, digitally assisted assembly, casting, additive manufacturing, composites, designing for manufacturing, testing and training. A world-class centre for advanced manufacturing 4 MANUFACTURING DONE BETTER 40x faster Lower cost Secured UK jobs Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) National reach High Value Manufacturing Catapult 5 The AMRC is a core part of the High Value Manufacturing Catapult, an alliance of leading manufacturing research centres backed by the UK’s innovation agency, Innovate UK. The High Value Manufacturing (HVM) Catapult is a thriving alliance that works with companies of all sizes to bridge the gap in – and accelerate the activity between – technology concept and commercialisation. Being part of the Catapult ensures that we play a core role in the revival of the national manufacturing sector. Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Manufacturing Capability Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Setting the scene Why do we need new propulsion technologies? Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Turboprop 14 Praga Alfa SM-92T Dornier 228 ATR 72-600 No of passengers 6 19 44-78 Range 750NM 650NM 740NM T/O power 500kW 2 x 540kW 2 x 2MW More efficient than turbofan Slower cruising speed Lower altitude operation Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Piston-prop 15 Britten-Norman Islander HAV Airlander 10 No of passengers 4-9 Up to 100 Range 675NM 4000NM T/O power 2 x 220kW 4 x 400kW More efficient than turboprop Cheaper operating costs Wider range of fuels Low speed & altitude operation Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Other variants 16 Image source: Internation council on clean transportation Image source: Eurocontrol Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Technology developments Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Battery electric 18 Image source: MagniX Image source Evolito Rolls-Royce Spirit of Innovation 400kW peak power 385.4mph Lilium Jet eVTOL Up to 6 passenger 30 ducted fan e-motors 100kW each Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Battery electric challenges 19 Image source: MagniX Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) 20 Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Battery technology 21 Spirit of Innovation Pack energy 72.9kWh Assume 400kW power requirement Run time approx. 10 minutes Mass: 450kg pack, 300kg cells Energy density approx. 160Wh/kg (0.5MJ/kg) 6480 cells Lithium-ion 3000mAh 15A continuous discharge 30A max, temp. limited Kerosene typically 43-48MJ/kg Other issues: Cooling Fire protection Packaging on aircraft Durability Charging time Critical minerals Li, Co State of art 1.2MJ/kg A320neo LHR-LIS 1565 km Estimated total fuel burn 3.6t 43MJ x 3,600kg = 154,800MJ Assume GT 50% efficiency = 77,400MJ required Assume 90% electric efficiency = 71.6t battery A320neo dry weight = 64t Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Ambition 22 Wright Spirit Retrofitted BAe 146 100 passengers Range approx. 1hr 4 x 2MW electric ducted fan motors 1000Wh/kg battery Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Fuel cell electric 23 Image source: ZeroAvia Proton exchange membrane (PEM) Fuel Cell Image source: TheSix Technology Solutions Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Hydrogen storage 30 11,000 litres Storage volume for 1kg hydrogen (142MJ) 14 litres 24 litres Atmospheric pressure Compressed at 700bar Liquid at -253°C 1kg Kerosene approx. 48MJ LH2 = 1/3 mass of kerosene But 4 times volume Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Hydrogen aircraft concepts 31 Also fully electric version 4 pods 6 FC stacks for 2.4MW 2.1MW motor EIS 2035 Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Hydrogen storage 32 Key challenges •Materials compatibility •Hydrogen embrittlement •Permeability •Cryogenic •Boil off •Sloshing •Gravimetric efficiency •System integration •Location on aircraft •Leakage Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Hydrogen combustion 33 Mitigation •New combustor/nozzle design •Higher creep resistance alloys •Improved hot corrosion resistance •Improved coating systems Challenges cf kerosene •Larger temperature gradients •Increased heat transfer of combustion products •Short quench distance •Increased water vapour •Hydrogen embrittlement 2022 trials on modified AE2100 turboprop 2023 Pearl jet engine combustor trials Full scale Pearl engine trails planned for 2025 Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Sustainable Aviation Fuels (SAF) 34 Various non-fossil based derivatives •Gen 1 produced from vegetable oils , crops •Gen 2 produced from biomass (e.g. waste wood) •Gen 3 synthetic fuels, power-to-liquid All essentially a drop-in fuel and can be blended Difficult to achieve true net zero Image source: Climatedrift.com Image source: Royal Society of Chemistry Image source: FOCA Potential other benefits of SAF Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Gas turbine developments 35 Ultra high bypass ratio (e.g. UltraFan) Open rotor/unducted fan (e.g. RISE) 140” fan diameter (ByPass Ratio 15:1) 25,000 to 100,000 lb thrust Carbon fibre fan blades with Ti leading edge & composite case (saves 700kg) Geared fan Turbine stages reduced from 10 to 6 Ceramic matrix composites Additive Manufacturing 10% more efficient than Trent XWB 100% SAF compatible ByPass Ratio up to 20:1 Single rotating fan plus variable pitch deswirling vanes All composite fan blades Advanced metal alloys and CMCs Additive manufacturing 20% efficiency improvement target 100% SAF compatible Potentially compatible with hydrogen Advanced hybrid (SWITCH) Dual spool geared turbofan Hybrid-electric Water Enhanced Turbofan (WET) 20% improvement in fuel burn 50% reduction in climate impact (CO2, NOx, contrails) 100% SAF compatible Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Hybrid solutions 36 Partially distributed Fully distributed Hybrid system introduces mass challenge, but potentially unlocks specific fuel consumption benefits The scale of the benefits is still unclear, but the underlying battery and motor technologies are key enablers. Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) Propulsion system options 37 Image source: ATI FlyZero Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) External factors Confidential. Copyright © The University of Sheffield AMRC 2023. Template: AMRC.PPTW – Revision 7 (Feb 2023) External factors and considerations 39 Fuel prices Scalability of fuels Green energy, green hydrogen Global legislation and policy (USA oil & gas, crops) Airport infrastructure - globally Supply chain: critical raw materials, carbon boarders adjustment mechanism New platforms to install new technology Certification of new technology