Document
ABSTRACT: Technologies for Aircraft Noise Reduction By Dennis Huff NASA Glenn Research Center Technologies for aircraft noise reduction have been developed by NASA over the past 15 years through the Advanced Subsonic Technology (AST) Noise Reduction Program and the Quiet Aircraft Technology (QAT) project. This presentation summarizes highlights from these programs and anticipated noise reduction benefits for communities surrounding airports. Historical progress in noise reduction and technologies available for future aircraft/engine development are identified. Technologies address aircraft/engine components including fans, exhaust nozzles, landing gear, and flap systems. New “chevron” nozzles have been developed and implemented on several aircraft in production today that provide significant jet noise reduction. New engines using Ultra-High Bypass (UHB) ratios are projected to provide about 10 EPNdB (Effective Perceived Noise Level in decibels) engine noise reduction relative to the average fleet that was flying in 1997. Audio files are embedded in the presentation that estimate the sound levels for a 35,000 pound thrust engine for takeoff and approach power conditions. The predictions are based on actual model scale data that was obtained by NASA. Finally, conceptual pictures are shown that look toward future aircraft/propulsion systems that might be used to obtain further noise reduction.
www.nasa.gov
Dennis L. Huff
Cleveland, Ohio
February 16, 2006
Chief, Acoustics Branch
NASA Glenn Research Center
West Park Airport Committee Meeting
Technologies for Aircraft Noise Reduction
National Aeronautics and Space Administration www.nasa.gov
QAT Technology Benefit (Quiet Aircraft Technology)
10 dB reduction 65 dB contour is within airport Enables projected air travel growth Reduces community noise impact
• • • •
expectations Doesn’t meet public Constrained growth 5 dB Reduction (TRL 6)
AST Technology Benefit
• • •
(Advanced Subsonic Technology) 55 dB 65 dB Airport
Key
Miles
Technology Benefit: Reduced Noise Exposure
1997 Baseline
National Aeronautics and Space Administration www.nasa.gov Stage 4 Future Goals NASA Goals for Technology Development 777-200 A330-300 A320-200 MD-11 A300-600R MD-90-30 Current 747-400 MD-87 MD-82 767-300ER A310-300 757-200 B-747-300 A300B4-620
Year of Certification
Stage 3 A310-222 JT8D-200,PW2000,PW4000,V2500,GE90,PW6000 MD-80 B-747-200 B-747-SP A300
To Meet Future Requirements
DC-10-40 Average in Service B-747-200 B-737-200
New Technology Enables Aircraft
B-747-200 B-737-200 B-727-200 History B-747-100 Stage 2 B-727-100 DC9-10 JT3D, JT8D, JT9D,CF6,CFM56 B-727-100 0.0 10.0 -20.0 -10.0 National Aeronautics and Space Administration
Average Noise Level Relative to Stage 3 (EPNdB)
ZRH www.nasa.gov LGA SEA JFK EWR ATL MSP DTW PIT ORD SFO MCO LAX CVG BOS DFW IAD 0 5 10 15 20 25 30 35 40 45 50
Aircraft Fleet Noise Reduction Needed For
55 LDN Noise Contours Within Airport Boundaries
EPNdB
Reduction,
Fleet Noise
According to a document from the U.S. Environmental Protection Agency (EPA) published in the 1970’s, 55 LDN is the outdoor noise exposure level "requisite to protect the public health and welfare with an adequate margin of safety". The phrase "health and welfare" is defined as "complete physical, mental and social well-being and not merely the absence of disease and infirmity".
National Aeronautics and Space Administration
Analysis by Don Garber, NASA Langley, using NoiseMap
www.nasa.gov
• Fan Noise • Jet Noise
Engine Noise
Aircraft Operations
Aircraft Goal: 10 dB Quieter than 1997 Technology
NASA’s Noise Reduction Research Programs
National Aeronautics and Space Administration www.nasa.gov
AeroAcoustic Propulsion Lab
W8 Fan Rig
Major Engine Noise Test Facilities at NASA Glenn
Test Facilities Provide Component-Level Noise Assessments
9x15 Wind Tunnel
National Aeronautics and Space Administration www.nasa.gov
Exhaust
Turbine
Combustor
Compressor
(PW8000)
Engine Noise Sources
(P&W PW8000 Engine, Conceptual)
Stator
Fan
Inlet
National Aeronautics and Space Administration www.nasa.gov St ator Vane
Swept/Leaned Stators
Act ive V anes Inst alled on t he NASA, Glenn Act ive noise Cont rol Fan
Active Noise Control
Rotor Blade
Forward-Swept Fans
Noise Prediction
Scarf Inlets
Engine Noise Reduction Technologies
Chevron Nozzles
Higher Bypass Ratio
National Aeronautics and Space Administration www.nasa.gov
blowing air
internal blade passages
: 9x15 Wind Tunnel
Testbed
Trailing Edge Blowing
: ANCF Fan Rig (TRL 3)
Reduced Fan Noise
Testbed
Benefits: National Aeronautics and Space Administration www.nasa.gov
Trailing Edge Blowing – ANCF Demo
Click Here for Audio Demo
National Aeronautics and Space Administration www.nasa.gov
Jet Noise Reduction With Chevron Nozzles
National Aeronautics and Space Administration www.nasa.gov
Small Engine Test Supports
Business & Regional Jet Applications
Engine Noise Diagnostic Testing at Honeywell
Forward-Swept Fan Advanced acoustic liners
engine acoustic field
National Aeronautics and Space Administration Engine: Honeywell HTF7000 2005/06 Engine Tests Include: • Internal flow measurements • Microphone arrays to map • Fan noise modal measurements • In-situ impedance measurement Noise Reduction Technologies: • • www.nasa.gov Cruise Take-Off VAN
Planned for 2006
Wind Tunnel Fan Operability Test
Design of Low Noise Engine Initiated at P&W
Low Noise Because of: • Low fan tip speed • Low jet exhaust velocity Enabling Technologies: • Fan drive gear system • Variable area fan nozzle Additional Noise Reduction Advanced Technologies
Ultra-High Bypass “Advanced Geared Turbofan”
National Aeronautics and Space Administration www.nasa.gov
Flight Test In August 2005
Wind Tunnel Test
“Toboggan” Landing Gear Fairings
Reduced Gear Noise
Source Identification
Benefits: National Aeronautics and Space Administration www.nasa.gov
on wing in wind tunnel
Noise reduction devices mounted
Reduced Flap and Slat Noise
Benefits:
Cove Filler
Continuous Line Mold Flap & Slat
National Aeronautics and Space Administration
Low-Noise Wing Baseline: High Noise Regions
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Simulation of Sound Propagating to Ground
Accelerates to 110kts while Begins traveling south at 2000’ altitude in level flight, 110kts Slows to 50kts, and then descends at 50kts to 100’ Performs 90° CCW turn while moving eastward at 50kts climbing to 2000’ Travels east at 110kts, then turns 90° to south and then accelerates to 180kts – – – – –
Movie shows propagation of sound to grid of ground receiver locations
Rotorcraft (CH53E) flight description:
•
National Aeronautics and Space Administration www.nasa.gov Contact: Dennis L. Huff Chief, Acoustics Branch NASA Glenn Research Center
Hear the Quiet Airplanes of the Future
A major airframe/engine opportunity is a Boeing 737 replacement that will require ~ 35,000 lb thrust engines. Using the best noise reduction technologies under development now, what are the predicted noise levels for a new engine? This audio demonstration contains projected noise levels for an engine for simulated takeoff and approach power conditions. It is based on actual model scale jet and fan data taken in NASA’s wind tunnels.
• • •
National Aeronautics and Space Administration www.nasa.gov Airport
Aft
Boundary
Inlet
Airframe Advanced Engines & Take-Off Condition Relative to Current Fleet Average Predicted Source Noise Reduction
Audio Sequence
Current Fleet play sound demo:
Click on picture to
-8 -4 -24 -20 -16 -12 EPNdB
Quiet Airplanes of the Future
Fairings
Lower Fan Tip Speeds Lower Jet Exit Velocities Variable Area Nozzle “Soft” Fan Stator Vanes Fan Trailing Edge Blowing Bypass Acoustic Splitter “Toboggan” Landing Gear Continuous Mold Line Flap Slat Cove Filler Advanced Engines & Airframe • • • • • • • • • Airport Boundary Projected level required for objectionable noise to be contained within airport boundary.
National Aeronautics and Space Administration www.nasa.gov
Aft
Airport Boundary
Inlet
Advanced Engines & Airframe Approach Conditions Relative to Current Fleet Average Predicted Source Noise Reduction
Audio Sequence
Current Fleet play sound demo:
0 Click on picture to
-8 -4 -24 -20 -16 -12 EPNdB
Quiet Airplanes of the Future
Fairings
Lower Fan Tip Speeds Lower Jet Exit Velocities Variable Area Nozzle “Soft” Fan Stator Vanes Fan Trailing Edge Blowing Bypass Acoustic Splitter “Toboggan” Landing Gear Continuous Mold Line Flap Slat Cove Filler Advanced Engines & Airframe • • • • • • • • • Airport Boundary Projected level required for objectionable noise to be contained within airport boundary.
National Aeronautics and Space Administration www.nasa.gov
154.2”
Fan Diameter
Single Fan On Blended Wing Body (BWB)
National Aeronautics and Space Administration www.nasa.gov
105.1”
Fan Diameter
Dual Fan On Blended Wing Body (BWB)
National Aeronautics and Space Administration www.nasa.gov
Dual Fan – Conceptual Applications
National Aeronautics and Space Administration www.nasa.gov
Summary
developing technologies for aircraft noise reduction. identify opportunities to introduce new technologies into engines and aircraft. development with new vehicles. from existing aircraft to newer aircraft with better noise reduction technologies. combinations that can move the average 65 LDN noise contour near the airport boundaries if the entire fleet were replaced.
Considerable progress has been made over the past 15 years
NASA has been working closely with aerospace companies to Limited technologies are retrofit-able, most will require Benefits near airports are incremental due to slow turnover Technologies exist today to produce aircraft/engine
• • • • •
National Aeronautics and Space Administration