Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 1
National Aeronautics and Space Administration!
www.nasa.gov!
Propulsion Technologies for Future Aircraft Generations: Clean, Lean, Quiet, and Green!Dr. Rubén Del Rosario!Project Manager, Subsonic Fixed Wing!NASA John H. Glenn Research Center!Cleveland, OH USA!
3rd UTIAS International Workshop on Aviation and Climate Change Toronto, Canada!2-4 May 2012!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 2
Outline of Talk!
!Introduction!
!Major Challenges of Aviation!
!NASA Subsonic Transport Metrics Research!
!NASA Gen N+3 Advanced Vehicle Concept Studies!
!Alternative Fuels Research!
!MDAO Tools and Methods!
!Towards Electric Propulsion!
!Concluding Remarks!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 3
Major Challenges for Aviation!
Baseline!
CO
2 E
mis
sio
ns
2050
Technology Development—Ongoing Fleet Renewal!
Operational Improvements—ATC/NextGen/ !
Wit
h I
mp
rove
me
nt
Additional Technology Advancement!
Carbon neutral growth!
Baseline reduced by 50%!
and Low Carbon Fuels!
2020 2005
Carbon overlap!
By 2050, substantially reduce emissions of carbon and oxides of nitrogen and contain objectionable noise within the airport boundary!
Source: IATA, 2010!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 4
NASA Aeronautics ProgramsSubsonic Fixed Wing and other NASA Green Aviation emphasis
Fundamental Aeronautics Program
Aviation Safety Program
Airspace Systems Program Integrated Systems
Research Program
Aeronautics Test Program
Conduct fundamental research that will produce innovative concepts, tools, and technologies to enable revolutionary changes for vehicles that fly in all speed regimes.!
Conduct cutting-edge research that will produce innovative concepts, tools, and technologies to improve
the intrinsic safety attributes of current and future aircraft.!
Directly address the fundamental ATM research needs for NextGen by
developing revolutionary concepts, !capabilities, and technologies that !
will enable significant increases !in the capacity, efficiency and !
flexibility of the NAS.!
Conduct research at an integrated !system-level on promising concepts and
technologies and explore/assess/demonstrate the benefits in a relevant environment!
Preserve and promote the testing capabilities of one of the United States’ largest, most versatile
and comprehensive set of flight and ground-based research facilities.!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 5
SFW Strategic Framework/Linkage!
Strategic Thrusts
1. Energy Efficiency
2. Environmental Compatibility
Strategic Goals
1.1 Reduce the energy intensity of air transportation
2.1 Reduce the impact of aircraft on air quality around airports
2.2 Contain objectionable aircraft noise within airport boundaries
2.3 Reduce the impact of aircraft operations on global climate
System Level Metrics
• Fuel Burn • Energy Efficiency
• LTO NOX Emissions • Other LTO Emissions • Aircraft Certification
Noise • Cruise NOX Emissions • Life-cycle CO2e per
Unit of Energy Used
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 6
The NASA Subsonic Fixed Wing Project!Explore and Develop Tools, Technologies, and Concepts for!
Improved Energy Efficiency and Environmental Compatibility for! Sustained Growth of Commercial Aviation!
Objectives!§ Prediction and analysis tools for reduced uncertainty!§ Concepts and technologies for dramatic improvements in noise, emissions
and performance Relevance !§ Address daunting energy and environmental challenges for aviation!§ Enable growth in mobility/aviation/transportation!§ Subsonic air transportation vital to our economy and quality of life !Evolution of Subsonic Transports Transports
1903! 1950s!1930s! 2000s!
DC-‐3 B-‐787 B-‐707
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 7
NASA Subsonic Transport System Level Metrics…. technology for dramatically improving noise, emissions, & performance!
Research addressing revolutionary N+3 Goals with opportunities for near term impact
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 8
Boeing, GE, GA Tech
Advanced concept studies for commercial subsonic transport aircraft for 2030-35 EIS
Copyright, The McGraw-Hill Companies. Used with permission.
NG, RR, Tufts, Sensis, Spirit
GE, Cessna, GA Tech
MIT, Aurora, P&W, Aerodyne NASA,
VA Tech, GT
Goal-Driven Advanced Vehicle Concept Studies (N+3)summary!
Advances required on multiple fronts…!
Trends:!• Tailored/Multifunctional Structures!• High AR/Active Structural Control!
• Highly Integrated Propulsion Systems!
• Ultra-high BPR (20+ w/ small cores)!
• Alternative fuels and emerging hybrid electric concepts!
• Noise reduction by component, configuration, and operations!
NASA
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 9
Technical Challenges!
Diversified Portfolio Addressing N+3 Goals broadly applicable subsystems technical challenges!
N+3 Vehicle!
Concepts!
Tailored Fuselage
Tools
High AR Elastic Wing
Propulsion Airframe
Integration
Hybrid Electric
Propulsion
Alternative Fuels
Quiet, Simplified High-Lift
Research Areas!
High Eff. Small Gas Generator
SX/PX Rim 1500F
PM Bore 1300F
Reduce Drag, Weight, TSEC, Emissions and Noise!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 10
High Efficiency Small Gas Generator versatile core applicable to variety of propulsion systems!
Objective !Explore and develop technologies to enable advanced, small, gas-turbine generators with high thermal efficiency!
Technical Areas!
Hot Section Materials!
Tip/Endwall Aerodynamics!
Fuel-Flexible Combustion!
Decentralized Control!
Core Noise!
Benefit/Pay-off!– BPR 20+ growth by minimizing core size!
– Low emission, fuel-flexible combustors with NOx reduction of 80% below CAEP6!
!
!
!
TSEC Clean Weight Drag Noise
hybrid system ducted fan open fan
multi-point lean direct injection
materials, aerodynamics, acoustics, and control
Unsteady Pressure & Temperature!
Understanding Core Noise Generation!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 11
adaptive fan blades
Objective !Explore and develop technologies to enable highly coupled, synergistic aero-propulsive-control!
Technical Areas!
Aerodynamic Configuration!
Adaptive, Lightweight Fan Blade!
Distortion-Tolerant Fan!
Acoustic Liners!
Propulsion Airframe Aeroacoustics!
Benefit/Pay-off!
– Improved multidisciplinary performance and noise characteristics; benefits tradable for specific missions!
!
!
!
Propulsion Airframe Integrationincreasingly synergistic integration!
TSEC Clean Weight Drag Noise
boundary-layer ingesting concepts thrust vectoring
distortion tolerance
jet/surface interaction acoustics
Aeroelastic Analysis of Distortion Tolerant Fan!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 12
Alternative Fuels characterization of alternative fuels in the near- and mid-term!
Objective !Fundamental characterization of alternative fuel properties and emissions to reduce impact of aviation on the environment!
Technical Areas!
Fuel Property Characterization!
Emission & Performance Characterization!
Benefit/Pay-off!
– Broad use and understanding of alternative aviation fuels!
– Low emission, fuel-flexible combustors with NOx reduction of 80% below CAEP6!
– Reduce aircraft engine particulate matters and gas phase emissions!
!
!
!
TSEC Clean Weight Drag Noise
Alternative Aviation Fuel Experiment!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 13
open Source MDAO engineering framework
Tools cross-cutting and foundational!
Objective !Explore and develop tools for the practical design, analysis, optimization, and validation of technology solutions for components and vehicle systems !
Technical Areas!
MDAO!
Systems Analysis/Conceptual Design!
Physics-based!
Benefit/Pay-off!
– High confidence, cost-effective variable-fidelity tools available for analysis and design from subcomponents to full vehicle systems!
!
!
!
TSEC Clean Weight Drag Noise
Vehicle Sketch Pad geometry
high-fidelity tools/models and validation experiments
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 14
MDAO Tools & Methods!
Focus: Develop an advanced, open source MDAO framework enabling the integration of multi-fidelity, multi-disciplinary design and analysis tools!
Technical Content:!Open Source Framework Development (OpenMDAO): Continue development of open-source, Python-based multi-disciplinary engineering framework leading to initial “full” release (V1.0) !!Geometry Development: NRA-led activity focused on the development of a geometry handling capability within the OpenMDAO framework. (NRA participants – MIT & University of Michigan) !!MDAO Evaluation/Test Problem Formulation: Exercise existing OpenMDAO integration capabilities through a series of aerospace related test problems, included herein will be combustion & structure related activities!!GEN2 MDAO Framework Validation: Validation of ModelCenter-based framework by assessing predictive capability of integrated set of design/analysis tools on state-of-the-art commercial transport (B787)!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 15
Sample of MDAO Tools & Methods Work (1)!
Conventional B737-800
w/CFM56-7B26 engine
Unconventional BWB-710
w/advanced 3-shaft engine
Metric % Diff Goal % Diff Goal
Takeoff Gross Weight -‐3.1% ± 5% +2.0% ± 15%
Range -‐0.1% ± 2.5% -‐1.2% ± 10%
Takeoff Field Length -‐4.2% ± 5% +7.1% ± 15%
Landing Field Length +2.3% ± 5% +10.7% ± 15%
LTO NOx -‐5.8% ± 5% No Validation Data ± 15%
Avg EPNL +2.1 dB ± 2.5 dB No Validation Data ± 7.5 dB
Conventional Unconventional
GEN2 MDAO Tool Suite Validation!- 2nd generation capability developed primarily to analyze unconventional systems!- Validation completed by comparing aircraft weight/performance for both configurations against independent data sources !- Predicted values met, or nearly met, accuracy targets for all metrics for both architectures!
GEN2 MDAO Tool Suite - HWB
Comparison of Prediction vs. Available Data
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 16
Sample of MDAO Tools & Methods Work (2)!
OpenMDAO Application Problem – Lean Direct Injection Combustor!- Develop parametric-CAD approach for LDI combustor design!- Quantify influence of key aerothermodynamic variables on individual & coupled injector performance!- Investigate parametric-CAD approach to Hi-Fidelity (CFD) design-by-analysis addressing issues of geometry handling, automated meshing and Low/Hi-fidelity code coupling!
Flow Diagram of Envisioned Process
Geometry Handling
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 17
superconducting turbogenerators
Objective !Explore and develop technologies to enable hybrid gas-turbine/electric propulsion architectures!
Technical Areas!
Transmission and Winding Materials!
Gas-Turbine/Electric Hybrids!
Aircraft Power Distribution!
Benefit/Pay-off!
– Low noise and zero emission (onboard) electric drives!
– Renewable energy sources for aviation use!
– Electric transmission to enable decoupled distributed propulsion!
!
!
!
Hybrid Electric Propulsionchanging the paradigm!
single power source to multiple, decoupled fans
stable, wide area power transmission
dual power to single fan
TSEC Clean Weight Drag Noise
adv conventional to hybrid to (eventually) all electric
Adv Motor & Gearbox
superconducting motor-drive fans
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Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
• Distributed propulsion for aircraft is the spanwise distribution of the propulsive thrust stream that maximizes the overall vehicle efficiency such as increase lift, reduce drag, or reduce aircraft weight.!
• In order to achieve maximum benefits, it will be necessary to design an aircraft with greater emphasis on propulsion airframe integration right from the conceptual design stage. !
Definition of Distributed Propulsion!
19 Subsonic Fixed Wing Project!Fundamental Aeronautics Program!
Propulsors ingest boundary layer & fill center-body wake. !
Turboelectric Distributed Propulsion (TeDP)!
Forward and aft fan noise shielding by airframe.!
Many small fans give a large total fan area and very high effective bypass ratio!
Low velocity core exhaust reduces noise. !
Large efficient engines with freestream inlets drive superconducting generators.!
Electric power from generators distributed to multiple motor-driven propulsors.!
20
Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
Benefits of Turboelectric Distributed Propulsion!
• Decoupling of propulsors from power generation enables!! !- Choice of propulsor(s)!! !- Choice of power source(s)!
• Optimal location for propulsor and power source (e.g. wing-tip core/generator, embedded fans, power storage)!
• With inverters, electrical system functions as a continuously variable ratio transmission!
• Propulsion augmented vehicle control!– Constant power means no turbogenerator throttling!– Insensitive to aircraft speed!– Electric driven blowers for tail, elevator, aileron blowing in addition to vectored
thrust!• Greatly reduced FOD or turbine burst damage to airframe!
– Fans are shielded by fuselage with high redundancy (HWB only)!– Core compressors shielded by stationary generator housing!
• Possibility of emergency power generation by wind-milling the fans !
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Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
“N+3” UHB Podded HWB!
Composite Wings & Tails -‐146,100 lbs
Fuel Burn = 133,700 lbs
LFC (Centerbody)
HWB w/Composite Centerbody
PRSEUS
Advanced UHB Geared Turbofan
HLFC on Outer Wings and Nacelles)
Subsystem Improvements
-‐52%
Riblets, Variable TE Camber
Potential Fuel Burn Reduction – Initial Study!
Graph Not to Scale
Reference Fuel Burn = 279,800 lbs “777-200LR-like” Vehicle!
N3-X TeDP (LH2-cooled)!
HWB w/Composite Centerbody
Advanced Turboelectric Distributed Propulsion w/Boundary Level IngesWon
-‐201,300 lbs
Fuel Burn = 78,500 lbs
Wake Fill-‐in
LFC (Centerbody)
Composite Wings & Tails
PRSEUS
HLFC on Outer Wings and Nacelles)
Subsystem Improvements
-‐72%
Riblets, Variable TE Camber
HWB w/Composite Centerbody
Advanced Turboelectric Distributed Propulsion w/Boundary Layer IngesWon
N3-X TeDP (Cryo-cooled)!
-‐196,300 lbs
Fuel Burn = 83,500 lbs
Wake Fill-‐in
LFC (Centerbody)
Composite Wings & Tails
PRSEUS HLFC on Outer Wings and Nacelles)
Subsystem Improvements
-‐70%
Riblets, Variable TE Camber
22
Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
Turboelectric Distributed Propulsion Scalability!
737-Class CESTOL Aircraft (~170 pax)
777-Class Aircraft (+300 pax)
A380-Class Aircraft (+500 pax)
2-engine operation from small to very large aircraft is possible.
Small Regional STOL Aircraft (~150 pax)
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 23
Boeing/GE SUGAR “Volt”!
High Aspect Ratio Truss Braced Wing!Hybrid Electric (Batteries) Propulsion Systems!
NASA-CR-2011-216847!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 24
24 24 24
SUGAR Volt – Opportunities!
§ With a 750 Wh/kg battery, increasing aircraft weight to accommodate higher battery capacity reduces fuel burn and total energy
§ >500 WH/kg battery technology needed to meet NASA fuel burn goal
§ 85-90% fuel burn reduction is
max. achievable for SUGAR hybrid architecture and assumptions
240,000
220,000
200,000 180,000
163,000
1000
750
500
0257912
14161821232528303235
3739424446
90 100 110 120 130 140 150 160 170
Millions of BTU's (900 NMI)
Bloc
k Fu
el P
er S
eat (
900
NMI)
50%
55%
60%
65%
70%
75%
80%
85%
90%
95%
100%Pe
rcen
t Fue
n Bu
rn R
educ
tion
NASA Goal
Ba5ery Wh/kg
TOGW Scaled hFan,
TOGW 163,100
Scaled hFan,
TOGW 179,700
Per
cent
Fue
l Bur
n R
educ
tion
Fuel burn reducIon reaches a limit due to taxi and gas turbine operaIon assumpIons
25
Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
SUGAR Phase II!
• Task 1 N+4 Study (Complete)!– Workshop Results & Recommendations!– Sized Performance for LNG Concepts!
• JP/Jet-A vs LNG, ducted vs unducted fans, hybrid SOFC, BLI propulsor!– Technology Plan Roadmaps!
• LNG engines, systems, and infrastructure, H2, LENR, BLI, unducted fans and advanced propellers, hybrid electric engines and batteries!
– N+4 Recommendations!• Hybrid Electric Refinement!
– Task 2.2 – HE Architecture Development!– Task 3.3 – HE NPSS Modeling Task Plan!
• Truss Braced Wing Status!– Task 2.1 – TBW Configuration Development!
• Wing MDO, wing design and analysis, fuselage and wing FEM!– Task 3.1 & 3.2 – Wind Tunnel Planning!
BLI – Boundary Layer IngesIon FEM – Structural Model HE – Hybrid Electric H2 -‐ Hydrogen JP – ConvenIonal Jet Fuel LNG – Liquefied Natural Gas MDO – OpImizaIon NPSS – Propulsion Model SOFC – Fuel Cell TBW – Truss Braced Wing
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 26
• Assess and improve fan and rotor noise prediction codes!
• Phase 2 of N+3 Advanced Concepts Studies NRA!
• Processing and publication of FAST-MAC data!
• Planning and execution of FAST-MAC2!
• Checkout and validation of W-6 single-spool turbine facility!
• Conduct cross-project turbulence modeling focused-research NRA !
• Complete design and fabrication of distortion-tolerant fan!
• Evaluate and publish exhaust measurement from the AAFEX-2 (APG) !
• Planning of ACCESS flight using alternative fuels (FT and Biofuels)!
Major Ongoing SFW Activities!
Fundamental Aeronautics Program!Subsonic Fixed Wing Project! 27
SFW Project Summary!
• Addressing the environmental challenges and improving the performance of subsonic aircraft !
• Exciting exploration of the possible technological solutions with paths for maturation of technologies!
• Understanding and assessing the game changers of the future!
• Exciting challenges for an industry that was deemed as being “mature”!
• Strong foundational research in partnership with industry, academia, and other Government agencies!
Technologies, Tools, Concepts and Knowledge
Your Title Here 28
29
Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
“N+3” UHB Podded HWB!
Composite Wings & Tails Δ Fuel Burn = -‐2%
-‐146,100 lbs
Fuel Burn = 133,700 lbs
LFC (Centerbody) ∆ Fuel Burn = -‐7%
HWB with Composite Centerbody ∆ Fuel Burn = -‐14%
PRSEUS Δ Fuel Burn = -‐3%
Advanced UHB Geared Turbofan Δ Fuel Burn = -‐14%
HLFC on Outer Wings and Nacelles) Δ Fuel Burn = -‐9%
Subsystem Improvements Δ Fuel Burn = -‐1%
-‐52%
Riblets, Variable TE Camber Δ Fuel Burn = -‐1%
PotenWal Fuel Burn ReducWon – IniWal NASA Study
Graph Not to Scale
Reference Fuel Burn = 279,800 lbs “777-200LR-like” Vehicle!
N3-X/TeDP LH2-cooled!
HWB with Composite Centerbody ∆ Fuel Burn = -‐14%
Advanced Turboelectric Distributed Propulsion With BLI Δ Fuel Burn = -‐35%
-‐201,300 lbs
Fuel Burn = 78,500 lbs
Wake Fill-‐in ∆ Fuel Burn = -‐4% LFC (Centerbody) ∆ Fuel Burn = -‐6%
Composite Wings & Tails Δ Fuel Burn = -‐2%
PRSEUS Δ Fuel Burn = -‐2% HLFC on Outer Wings and Nacelles) Δ Fuel Burn = -‐7%
Subsystem Improvements Δ Fuel Burn = -‐1%
-‐72%
Riblets, Variable TE Camber Δ Fuel Burn = -‐1%
HWB with Composite Centerbody ∆ Fuel Burn = -‐14%
Advanced Turboelectric Distributed Propulsion With BLI Δ Fuel Burn = -‐33%
N3-X/TeDP Cryo-cooled!
-‐196,300 lbs
Fuel Burn = 83,500 lbs
Wake Fill-‐in ∆ Fuel Burn = -‐4% LFC (Centerbody) ∆ Fuel Burn = -‐6%
Composite Wings & Tails Δ Fuel Burn = -‐2%
PRSEUS Δ Fuel Burn = -‐2% HLFC on Outer Wings and Nacelles) Δ Fuel Burn = -‐7%
Subsystem Improvements Δ Fuel Burn = -‐1%
-‐70%
Riblets, Variable TE Camber Δ Fuel Burn = -‐1%
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Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
Power Converter
• Electric drive distributes power with greater flexibility, lower stress and higher efficiency than gears • Enables electric actuation for controls, environmental management, etc.
Other applications: electric actuators, etc
Cooling Source (Three
Options)
Turboelectric Distributed Propulsion Layout
31
Fundamental Aeronautics Program!Subsonic Fixed Wing Project!
NASA’s Distributed Propulsion Concept (N3-‐X)
Superconducting-motor-driven fans in a continuous nacelle!
Wing-tip mounted superconducting !turbogenerators!
• TeDP-HWB: Turboelectric Distributed Propulsion – Hybrid Wing Body!• Two wingtip mounted turboshaft engines driving superconducting
generators!- Decoupled propulsive producing device from power producing device!
• Superconducting electrical transmissions!• Fifteen superconducting, motor driven propulsors embedded in fuselage!• Two cooling schemes: cryo-cooled and LH2-cooled!
