# Presentation: 188846

## AIRCRAFT EMISSIONS AND THE ENVIRONMENT

**AIRCRAFT EMISSIONS AND THE ENVIRONMENT**

**ICAO Actions on Emissions**

- Standard for Gaseous Emissions

- »

- unburned hydrocarbons

- »

- carbon monoxide

- »

- oxides of nitrogen

- CAEP 2 -

-  NOx

-  Reduction of 20%; effective 1996

- CAEP 4 -

- below 1996

- Improved Local Air Quality

- Improved Local Air Quality

- Ozone Depletion Recovery

- Ozone Depletion Recovery

- Global Warming Reversal

- Global Warming Reversal

***NASA Needs to Take the Leadership in Providing Achievable Aircraft Emissions***

***Reduction Technologies to Enable Continual Growth in Air Transportation***

## Emissions Goals/Benefits

- Reduce CO2 Emissions of Future Aircraft by 25% Within 10 Years,
-     by 50% Within 25 Years, and Possibly Totally Within 30 to 40 Years.
- Reduce NOx Emissions of Future Aircraft by a Factor of Three
-     Within 10 Years, by a Factor of Five Within 25 Years, and Possibly Totally Within 30 to 40 Years.

***Goals:***

***Benefits:***
*** ******Near term: Substantially mitigate aviation’s contribution to climate change and degradation of local air quality and the ozone layer.***
*** ******Far term: Significantly or totally eliminate aircraft emissions as a source of climate change and degradation of local air quality and the ozone layer.***

## Slide 3

## Environmental Program NOx Emission 

- Reduction Waterfall

**UEET Propulsion Element**

**Airframe Element**

- AST Technologies

_**Notional**_

**Non-Combustion**
**Propulsion System**

**NOx Goal 100% **
**(Proposed)**

- Environmental
- Compatiblity Initiatives

- R&T Base

**Three Pillar**
**NOx Goal 67%**
**( for Carbon-Based**
** ****Fuels)**

- AATT

## Environmental Program CO2 Emission 

- Environmental Program CO**2** Emission
- Reduction Waterfall

- Environmental
- Compatiblity Initiatives

**UEET Propulsion Element**

**Airframe Element**

**Non-Carbon-Based  **
**Fueled Aircraft Element**

- AST Technologies

_**Notional**_

**CO****2**** Goal 100 %**
**Non-Carbon Based**
**Fuels**
** ****(Proposed**
**30-40 Yr.Goal)**

**CO****2**** Goal 50 %**
**JP-type**
**Fuels**
** ****(Proposed**
**25 Yr.Goal)**

**CO****2**** Goal 25 %**
**JP-type**
**Fuels**
** ****(Proposed **
**10 Yr.Goal)**

- R&T Base

- AATT

## Program Goals

***Advanced Subsonic Technology (AST) Propulsion Program***
***Program Goals***

**Work with U.S. industry (GE Aircraft Engines, Pratt and Whitney, Allison**
**Engines, and AlliedSignal Engines) to provide technology readiness to**
**achieve reduced environmental impact of future propulsion system**

** ****Engine Systems Element **
** ****Fuel efficiency improvements of at least 8-10% and reduction **
**  ****of at least 3-10% in direct operating cost of air travel of new**
**  ****commercial engines to enter into service in 2005**
** ****Emissions Reduction Element**
** ****Demonstrate by 1999 reductions in LTO NOx emissions of at least**
**  ****50% of the 1996 ICAO limits for future large and  regional engine**
**  ****( 50:1 & 30:1 Pr ) combustors with corresponding reductions in**
**  ****cruise NOx levels, no increases in other  emission constituents (CO,**
**  ****smoke, and unburned hydrocarbons), and comparable operability**
**  ****and maintainability. (TRL 6/5)**
** ****Address new emission concerns with effort to understand the**
**  ****emission levels of aerosols and particulates coming from low**
**  ****emission combustors.**

## 	AST Propulsion 

**Higher Bypass Propulsor**
- - Improved low noise fan (part of Noise Element)
- - Improved lightweight static structure
-    materials & lifing TRL 6     3
- -  Fan bypass duct optimization TRL 4     2
- - Improved lubrication and health and usage
-    monitor for geared, very high-bypass engines TRL 4      2

**Reduced Emissions Combustor**
- -  Compact high pressure and
-    temperature combustor TRL 6     6/5

**Technologies required For 2005 Entry Into Service ****AST Very High Bypass Engines**

**High Efficiency Core**
- -  Improved turbomachinery aerodynamic,
-    aeroelastic, & film cooling codes TRL 6     3
- - Improved High OPR materials with
-    enhanced crack growth resistance TRL 5     3
- -  Improved controls technology  TRL 6     3

- 	AST Propulsion

**	****Advanced Subsonic Technology**

**TRL- 3**

**TRL- 4**

**TRL- 5**

**TRL- 6              **

**                                        **

**Certification and Entry Into Service**

**NASA Program Stops **

**and Industry Applies Technology to Their Products**

**COMPLEXITY**

**Maturity**

**Sector Combustor**

**Engine Test**

**TRL-3**

**TRL- 4**

**TRL-5**

**TRL - 6**

**TRL-9 **

**	****Advanced Subsonic Technology **

## AST 50 % NOx _x0008_Reduction Combustor Engine Testing

**Trent 760**

**Trent 800**

**GE90**

**1996 Regulation**

**PW4084**

**AST Large Engine**

** ****50% Reduction Goal**

**2004 Regulation**

**Lower Pressure**

**AST Engine Demo**

**Test Results TRL 6**

**Engine Demo Results**

***PROJECTED***

**  ****to AST**

**Engine Cycle  - TRL 6**

- •

** ****50% NOx reduction combustor demonstrated in a PW4000 development**

**engine, **

***emissions results projected to AST reduced fuel burn engine***

***cycle.***

- •

** ****Low emission combustion concept developed by Pratt & Whitney**

**  ****and NASA utilizes initially a rich front-end combustion followed by**

**  ****air quench and lean combustion.**

- •

** ****When combined with AST cycle fuel burn reductions, enables NOx**

**reductions to 50 %% of 1996 ICAO regulations over landing/take-off cycle.**

**  ****(See point marked AST Engine Testing on the figure showing the EPA**

**Parameter, grams of NOx per **

**kilonewton**

** ****of takeoff thrust, versus engine**

**pressure ratio.)**

- •

** ****This low emission combustor also provides comparable reductions of**

**   ****40% in cruise NOx emissions for AST engine cycle.**

- •

**Engine (TRL 6) and Full Annular Combustor testing (TRL 5)**

**  ****confirmed emissions, altitude**

** ****relight**

**, and lean blowout. Component**

**interactions, smoke, emissions,  and particulates with conventional**
**and low sulfur fuel were also measured and assessed.**

**AST 50 % NOx _x0008_Reduction Combustor Engine Testing**

** ****- Technology Readiness Level 6 **

## AST Emissions Reduction Element

- NO

- x

-  Technical Scorecard

***  ******GE - Large Engine Emissions Program***

- Upcoming Key Events

- •

- Sector Test Development of Altitude Relight: June - September 1999

- •

- TAPS Single Module Tests to 700 psia at NASA: April - October 1999

- •

- TAPS Full Annular Test at GEAE: November 1999

- •

- TAPS GE90 Engine Demo: March 2000

- Key Accomplishments

- TAPS: Twin Annular Premixing Swirler

- •

- TAPS 50 OPR Subcomponent Testing Demonstrated

- -

- NO

- x

-  58% Below the 1996 ICAO Standard

- -

- CO / HC 80% Below the 1996 ICAO Standard

- -

- Cruise NO

- x

-  75% Below GE90 Engine

- -

- No Autoignition in Premixer

- -

- Acceptable Lean Stability, Ground Ignition

- -

- Improved Cooling Technology with 40% Less Cooling

- •

- TAPS Development Potential for NO

- x

-  70% Below ICAO

- •

- TAPS Annular Hardware being Procured for Fall Test

- TAPS Mixer / Combustor

- 60

- degree,

- dual

- annular,

- TAPS

- sector

- built

- up

- in

- test

- rig.

- This

- low

- pressure

- sector

- used

- to

- test

- low

- power

- emissions,

- ignition,

- and

- lean

- stability.

- Shown

- in

- Mod

- 1

- configuration,

- currently

- being

- reconfigured

- to

- Mod 2 for testing in April.

- LTO NOx Emissions

- (% of 1996 ICAO)

**Open Symbols - Estimated**

**Closed Symbols - Measured**

**50%  Reduction**

- CFD Studies

- TAPS Annular

- 20%

- 30%

- 40%

- 50%

- 60%

- 70%

- 80%

- 90%

- 100%

- GEAE Ftube

- CE5 Ftube

- ASCR Ftube

- TAPS Ftube

- TAPS Sector

- TAPS ASCR

- TAPS Sector

**Advanced Subsonic Technology **

**AST Emissions Reduction Element**

## 	AST Emissions Reduction Element

_**PROGRESS AND ACCOMPLISHMENTS IN NASA AST PROGRAM**_
** ****Approach:**  Develop low emission technology through application of advanced analytical tools,
-                      component testing and full annular combustor demonstration
**Accomplishments:**
-  Two Allison single module flame tube configurations tested at NASA Glenn Facilities
** **Low emission combustion concept utilizes lean partially premixed injection
-    with a piloted axial airblast atomize/mixer.
-  Concept 1 Sector Combustor  tested at lower pressure at Allison with 50%NOx Reduction Levels
-  Five mixing module/combustor configurations tested and most promising design downselected
-   Higher Pressure Sector testing will be completed in FY99 at NASA Glenn

- AST Sector Combustor Concept 1

- Module NOx Reduction

**	****Advanced Subsonic Technology **

- 	AST Emissions Reduction Element

## Status of Low-Emission Combustor Technology for Subsonic Engines

**FY96**

**FY97**

**FY98**

**FY99**

**Fiscal Year**

**Percent of 1996 ICAO**
**LTO  Emissions Level  **

**Low Pressure Sector**
**Combustor Tests**

**Full Annular**
**Combustor Tests**

**Combustor**
**Engine Tests**

**Low Pressure**
**Flametube Tests**

**70% NOx Reduction**

**50% NOx Reduction**

**High Pressure**
**Sector Combustor**
**Tests**

**Low Pressure Flametube**
** ****Tests for 70% NOx reduction**

**Status of Low-Emission Combustor Technology for Subsonic Engines**