Transcript Aircraft Engine Technology

International Civil Aviation Organization
Colloquium on Environmental Aspects of Aviation
Aircraft Emissions - The Way Forward
Willard Dodds, Chairman
ICCAIA Noise and Emissions Committee
Montreal, 9-11 April 2001
Elements of ICAO CAEP Approach
• Terms of Reference
– Technical Feasibility - Safety
– Environmental Benefit
– Economic Reasonableness
•
Environmental Balance/Tradeoffs
– Noise
– Climate Change
– Local Air Quality
•
Program Balance
– Source Reductions (Technology)
– Operational Measures (Airlines and ATC)
– Market Based Measures
Unique ICAO Resources Address Complex Issues
Emission Issues
Issue
• Climate Change
Key Species
- Carbon Dioxide (CO2)
- Water Vapor
- NOx
• Local Air Quality
- NOx
- Carbon Monoxide (CO)
- Unburned Hydrocarbon (HC)
- Smoke/Soot
Mitigation
- Fuel Efficiency
- Operational
Measures
- Combustor Design
- Combustor Design
- Operational
Measures
Local Air Quality
450
• Continuous emissions
reductions
400
• Required design/test
margins ensure that
certificated product
emissions are below ICAO
limits
% of ICAO Standards
• ICAO Data Bank provides
current emissions
certification data
Hydrocarbons
150
Carbon monoxide
Oxides of nitrogen
Smoke
100
50
0
Pre81
81-91
91-present
Year of Engine Certification
Ref: The Boeing Company
Climate Change
• Continuous fuel efficiency
improvements driven by
market forces
– Long term - open
emissions trading
– Near term - voluntary
programs
Fuel Efficiency Improvement is a Joint
Engine/Airframe Manufacturer Effort
90
PERCENT OF BASE YEAR
• Market based measures
are being considered by
ICAO
100
80
Current Engine
Improvements
Current Engine and
Airplane
70
60
Projected to 2020
50
40
30
20
1960
1970
1980
1990
2000
SOURCE: IATA Environmental Review 1996
70% Fuel Efficiency Improvement over 40 Years
2010
2020
CO2/NOx Trade
Higher engine pressure
ratio and bypass ratio
reduce CO2/improve fuel
efficiency (SFC) and
facilitate noise reduction
SFC
SFC (lb/lb-hr, or EI NOx)
•
0
10
20
30
40
Overall Pressure Ratio
50
60
CO2/NOx Trade
•
Higher engine pressure
ratio and bypass ratio
reduce CO2/improve fuel
efficiency (SFC) and
facilitate noise reduction
Higher pressure ratio
requires higher flame
temperature, increasing
NOx formation rate
NOX
SFC
SFC (lb/lb-hr, or EI NOx)
•
0
10
20
30
40
Overall Pressure Ratio
50
60
CO2/NOx Trade
Higher engine pressure
ratio and bypass ratio
reduce CO2/improve fuel
efficiency (SFC) and
facilitate noise reduction
•
Higher pressure ratio
requires higher flame
temperature, increasing
NOx formation rate
•
Better NOx technology
needed to avoid
increased emissions
NOX
SFC
SFC (lb/lb-hr, or EI NOx)
•
Improving Combustor
Technology
0
10
20
30
40
Overall Pressure Ratio
50
60
Emissions Technology Outlook
•
•
•
Continuous technology improvement has
substantially reduced all emissions from
modern engines
Government and industry emissions
reduction technology programs are
underway
Barriers to wider introduction of these
technologies:
– high development and certification investment
with low production volume
– durability, operability, reliability & production
cost risks
– environmental tradeoffs
– unclear policy objectives
– unrealistic short term technology expectations
•
ICAO WG 3 Long Term Goals Group is
addressing technology transition issues
Emissions Technology Expectations
• 17 ICCAIA - Working Group 3 Papers prepared for CAEP/5
• Papers support IPCC Special Report projection of 20% improvement
in fuel efficiency between 1997 and 2015
• NOx reduction technology is progressing faster than the IPCC
scenario for NOx emissions 30-50% below CAEP/2 limits by 2020
• Concerns relative to the rate of future progress due to
– uncertain research funding
– environmental and technological tradeoffs/priorities
– increasing challenge to improve on current technology
Summary and Conclusions
• ICAO is uniquely qualified to set aviation environmental standards
– Brings together resources to balance complex trade-offs
– Avoids proliferation of confusing, inconsistent and counterproductive local rules
– Globally harmonized approach for a global industry
• Manufacturers continually work to improve emissions technologies
– Need consistent and consolidated scientific basis for valid trade-off analyses
– Aircraft emissions reduction efforts should be part of a balanced program
including improved operational factors
– Successful long term research requires continuous support and consistent goals
• CAEP/6 Work Program has proper elements to move forward on local air
quality and climate