Assessing Alternative Fuels For Helicopter Operation

1. Assessing Alternative Fuels For Helicopter Operation Alexiou, Tsalavoutas, Pons, Aretakis, Roumeliotis, Mathioudakis Presented by A. Alexiou Laboratory of Thermal Turbomachines National Technical University of Athens

2. Acknowledgements Collaborative & Robust Engineering using Simulation Capability Enabling Next Design Optimisation Environmentally Compatible Air Transport System

3. Contents • INTRODUCTION • MODELLING ASPECTS • Mission Fuel Calculation • Simulation Environment • Helicopter-Engine Integrated Performance Model • Alternative Fuels • CASE STUDY • Engine Performance for Jet-A • Helicopter Performance for Jet-A • Effects of Alternative Fuels on Performance • SUMMARY & CONCLUSIONS

4. Introduction Fuel Impact On Operating Costs (http://www.iata.org/pressroom/facts_figures/fact_sheets/pages/fuel.aspx)

5. Introduction Global Man-Made CO2 Emissions (ACARE Beyond Vision 2020)

6. Introduction World Annual Traffic (Airbus GMF 2010-2029)

7. Introduction IATA VISION 2050Build a zero-emissions commercial aircraft within 50 years Targets • Carbon neutral growth from 2020 • 1.5% average annual improvement of fuel efficiency • 50% reduction of CO2 emissions by 2050 relative to 2005 levels Four-Pillar Strategy • Technology (IATA target is for 10% of the fuel used will be an alternative fuel by 2017) • Operations • Infrastructure • Economic measures

8. Introduction • Research is mainly focused on second or new generation bio-fuels (e.g. algae, jatropha and camelina). • Sustainable bio-fuels can reduce aviation’s net carbon contribution on a full life-cycle basis (60-85%). • Tests demonstrated that the use of bio-fuels as ‘drop-in’ fuels is technically sound and doesn’t require any major adaptation of the aircraft. • To date, aviation industry is cleared to use blends with up to 50% ‘synthetic’ kerosene derived from coal, gas or biomass and conventional jet fuel.

9. Introduction Objective Study the effect of alternative fuels on the performance of a medium utility helicopter Requirement A helicopter mission analysis tool with the capability to use different fuels

10. Contents • INTRODUCTION • MODELLING ASPECTS • Mission Fuel Calculation • Simulation Environment • Helicopter-Engine Integrated Performance Model • Alternative Fuels • CASE STUDY • Engine Performance for Jet-A • Helicopter Performance for Jet-A • Effects of Alternative Fuels on Performance • SUMMARY & CONCLUSIONS

11. Oil & Gas • SAR 1800 1600 1400 1200 1000 Altitude [m] 800 600 400 200 0 0 10 20 30 40 50 -200 Time (min) Mission Fuel Calculation Mission definition H/C Specification e.g. velocity, time for each segment • Take-Off weight • air bleed/power off-take 2 Air Intake losses Exhaust losses 1 H/C PERFORMANCE MODEL MISSION PROFILE H/C operating conditions 3 H/C new weight 4 6 7 ENGINE PERFORMANCE MODEL FUEL MODEL H/C requirements (power, air cabin off take, Nrotor) Fuel Flow Rate 5 Mission Fuel

12. Simulation Platform PROOSIS (PRopulsion Object-Oriented SImulation Software) • Object-Oriented • Steady State • Transient • Mixed-Fidelity • Multi-Disciplinary • Distributed • Multi-point Design • Off-Design • Test Analysis • Diagnostics • Sensitivity • Optimisation • Deck Generation

13. Simulation Platform • TURBO library of gas turbine components • Industry-accepted performance modelling techniques • Respects international standards in nomenclature, interface & OO programming

14. Simulation Platform • Total helicopter power • Main rotor power • Induced • Profile • Fuselage • Potential energy change • Tail rotor power • Customer power extraction • Gearbox power losses

15. Integrated Model Helicopter Component (black box or PROOSIS model) Integrated Helicopter-Engine Component Engine Component

16. Alternative Fuels • Erroneous fuel metering • Accelerated wear of fuel system O-rings/seals • Fuel degradation in long-term storage • High pressure fuel pump wear • Increased fire hazard PROOSIS TURBO library uses 3-D tables to calculate the caloric properties of the working fluid in the engine model generated with the NASA CEA software (no dissociation) • Low aromatics content • Absence of natural anti-oxidants • Low electrical conductivity • Poor lubrication properties FT: Fischer-Tropsch HRJ: Hydrotreated Renewable Jet GTL: Gas-to-Liquid

17. Contents • INTRODUCTION • MODELLING ASPECTS • Mission Fuel Calculation • Simulation Environment • Helicopter-Engine Integrated Performance Model • Alternative Fuels • CASE STUDY • Engine Performance for Jet-A • Helicopter Performance for Jet-A • Effects of Alternative Fuels on Performance • SUMMARY & CONCLUSIONS

18. Engine Performance Sea-level standard conditions

19. Engine Performance

20. Engine Performance

21. Engine Performance

22. Helicopter Performance

23. Helicopter Performance Jet-A / MTOW / STD

24. Helicopter Performance Jet-A / MTOW / STD

25. Helicopter Performance Jet-A / MTOW / SL / STD SR = Vx / Wfuel

26. Helicopter Performance Jet-A

27. Effects of Alternative Fuels Fixed PWSD (TOP for Jet-A) Fixed XNH (TOP rating)

28. Effects of Alternative Fuels

29. Effects of Alternative Fuels Cruise at Vbr [40’] Climb at Vbe & Vz,max [2’] Descent [4’] Take-Off [2’] Land [2’] Warm up at MCP [2’]

30. Effects of Alternative Fuels

31. Effects of Alternative Fuels

32. Effects of Alternative Fuels

33. Effects of Alternative Fuels

34. Effects of Alternative Fuels

35. Contents • INTRODUCTION • MODELLING ASPECTS • Mission Fuel Calculation • Simulation Environment • Helicopter-Engine Integrated Performance Model • Alternative Fuels • CASE STUDY • Engine Performance for Jet-A • Helicopter Performance for Jet-A • Effects of Alternative Fuels on Performance • SUMMARY & CONCLUSIONS

36. Summary & Conclusions • An integrated performance model of a helicopter and its turboshaft engine has been created in an object-oriented simulation environment to study the effects of alternative fuels on helicopter operation. • For the fuels considered in this study there are no significant effects on the engine cycle compared to Jet-A except for the fuel flow rate that changes according to the difference of each fuel’s lower heating value from the reference one. • Considering the helicopter in a mission, there is an added effect from the differences in density between the fuels that modifies the helicopter’s payload-range capability. • Based on the modelling assumptions, the blended fuel appears at the moment as the most suitable choice for the aspects considered in the presented analysis (e.g. taking into account its effects on engine cycle parameters and helicopter operational characteristics) but other parameters should also be taken into account to allow for a more complete assessment (e.g. economics of fuel production, emissions, etc.).

37. Summary & Conclusions ATLAS Aero-TooLs for Advanced Simulations • The method presented herein can be further extended by including models of other disciplines in the existing integrated model (e.g. economics, noise and particulate emissions, etc.). This would allow the required multi-disciplinary calculations (including design and optimisation) to be performed in a single simulation environment with all the associated benefits that such an approach offers (configuration management control, transparent exchange of information between modules, common modelling standards, flexible mathematical model handling, etc.). • Finally, by creating a library of specific aircrafts (rotary or fixed wing) and a corresponding one with engines (turboshafts, turbofans, etc.) one can perform such studies for various combinations of current and future aircraft-engine models. Library of Gas Turbine Engines

38. THANK YOU Laboratory of Thermal Turbomachines National Technical University of Athens

40. Mission – engine performance

41. Alternative Fuels