Environmental Control Systems and the Cabin...

Air Quality ConferenceLondon, 2003

Air Quality in Passenger Aircraft

Environmental Control Environmental Control Systems and the Cabin Systems and the Cabin

EnvironmentEnvironmentAngus MacLean

Head of Marketing,Honeywell Aerospace Yeovil

October, 2003RAeS, London

Honeywell


Agenda

•Background to the Issue•Honeywell and “CabinAir”•Relationship between the issue and the ECS•Cure or Treatment?•Treatment Options•Conclusions


BackgroundAir Quality a Recognised Global Issue• Australian Senate report

– further investigation needed to pinpoint the exact cause of fumes - problem occurs on more than one aircraft type.

• UK House of Lords Select Committee– 50 Recommendations for adoption to enhance crew/passenger comfort

• CabinAir and other initiatives launched by EC– Public concern – Pre-normative standards

• U.S. National Research Council– Issued Recommendations and Concerns

• American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) research project 1262-TRP:– Relates air quality and other factors to comfort and health related symptoms reported by

passengers and crew on commercial transport aircraft.– The project is in 3 parts: Literature review, in-flight questionnaire and cabin air testing

ISSUE UNDER SIGNIFICANT GLOBAL SCRUTINY


Agenda



CabinAir

Honeywell Aerospace Yeovil, leader of Work Package 2

Objectives:1- To evaluate the impact & influence of the ECS on CAQ2- To identify opportunities to reduce the environmentalimpact of the ECS and associated sub-systems3- To identify innovative designs and technical solutions 4- To examine alternative modes of ECS operation5- To identify opportunities for retrofitting existing fleet


Key Findings of “CabinAir” Work Package 2The Work Package has identified:-

1- The effect upon CAQ by the ECS is limited to thermal parameters. Additional filtration and enhanced distribution can have a detrimental effect on performance.

2- Areas of greatest environmental impact, using a complex parametric model:-

bleed air pre-conditioning systemair-conditioning system

3- Innovative designs identified as being feasible:-zero bleed (including vapour cycle refrigeration)supplementary bleed / enhanced bleed managementenergy recoveryenhanced water separation (currently under demonstration)


Key Findings of “CabinAir” Work Package 2(continued)

4- Alternative operational procedures on the ground (Essen University) included central conditioned air source at the gate and mobile facility on the ramp. Neither concept involves localburning of hydrocarbon fuel.

5- Retrofit of additional equipment is subject to STC. WP2 findings support need for simultaneous Honeywell developments aimed at addressing in-service aircraft

WP 2 FINDINGS FOR NOVEL CONCEPTS CONTRIBUTETO PROPOSAL FOR PRE-NORMATIVE STANDARDS


Current ECS Configuration

CFE

3-15

Ram airoverboard

High pressureground connection

IntegratedController

FLIGHTDECK

FORWARDCABIN

Ram airinlet

REARCABIN

APU

APU inlet

IP HP

Air turbine starter

1-3

IP HP

Air turbine starter

CFE

ECS LHpack

ECS RHpack

Firewall

Pressurebulkhead

Mixingunit

Firewall

Firewall

Outside AirCompression

Pre-conditioningsystem

Air conditioningsystem

Distributionsystem

Recirculationsystem CPCS

CABIN AIR DEPENDENT ON OUTSIDE AIR CABIN AIR DEPENDENT ON OUTSIDE AIR


Agenda

•Background to the Issue•Honeywell and “CabinAir•Relationship between the issue and the ECS•Cure or Treatment?•Treatment Options•Conclusions


Cabin Air Quality - Affected by Outside Air

Deicing Ambient Air Pollution Engine Exhaust

Gate Operations

Refueling

IngestionandLeaks

Fuel Smell atEngine Start,

Takeoff

MULTIPLE SOURCES MAY AFFECT CABIN AIR

MULTIPLE SOURCES MAY AFFECT CABIN AIR


Existing Cabin Air Quality Standards

FAA / JAA regulations exist for:–Ventilation (0.55 lb air/min/pax)–Carbon monoxide & carbon dioxide (defined

concentration limits)–Ozone (defined concentration limits)–Temperature (minima & maxima for certain modes

of flight, and rates of pull-up/pull-down) –Cabin pressure (equivalent cabin altitude must not

exceed 8000ft)

NO REGULATION FOR OTHER CONTAMINANTS OR HUMIDITY


Agenda



Improving Cabin Air QualityCure or Treatment?

Prevention of root cause:Prevent unwanted compounds from entering bleed air

• Always a possibility of leaks or fluid ingestion• Impossible to control outside air (odours, ozone and

contaminants)Treatment of root cause

Removal of fluids and odours after entering bleed air• Use air quality devices• Use higher recirc ratio (dilutes unwanted compounds)• Integrate sensors and diagnostics for fault trend monitoring and

isolation

CANNOT PREVENT; TREAT WHERE FEASIBLE


Agenda



Honeywell Air Quality Products

• Controls (partner or acquire Dehumidification capability)• Desiccants• Refrigeration

Systems Solution

• Integrated Controls• Standalone Economizers with Demand Control Ventilation for buildings

Honeywell Air Quality Products Are Well Known in the IndustryHoneywell Air Quality Products Are Well Known in the Industry

Humidity Control

Hom

e an

d B

uild

ings

Ventilation• Heat/Energy Recovery Ventilators• Controls• (Partner or Acquire Blower capability)

Filtration• Electrostatic Precipitation air cleaners• Sorbent Media• Media Filtration (Partner or Acquire)

Ultraviolet Air Treatment

• UV Return Air• UV Coil Irradiation (Partner or Acquire)

• Ozone Converters (Available for new platforms and for retrofit of existing fleet

OzoneControl

Aer

ospa

ce

• International Space Station and other Space applicationsAir Revitalization Systems


Honeywell Technologies Under DevelopmentCatalytic Precooler

• Dual Function - Precooler and Ozone Converter• Future - Potentially Add CHOC

• Dual Function - Removes Both Ozone and Hydrocarbons From Bleed Air

• Low Temperature version of the CHOC

Aerosol Trap

• Reduces Odors Caused by Oil, Hydraulic Fluids, and Other Leaks Into the Cabin

CHOC -Combined Hydrocarbon & Ozone Converter

PCO -Photo Catalytic Oxidation

• Absorbs High Level Contaminants• Destroys Steady State Level Contaminants• Eliminates Odors• Disinfects Air via UV Enhanced Filtration• Destroys Microorganisms

Air Quality Monitors

• Bleed Air Monitor Measures Intensity of Contaminants

• Dual Function – Destroys Chemical & Biological• Provides Protection for Military & Buildings

NBC - Nuclear, Biological, Chemical Protection

Trend-Setting Technologies Are Ready for Industry IntroductionTrend-Setting Technologies Are Ready for Industry Introduction


Odours and Carbon Monoxide• Odours are largely hydrocarbons, causing perception of poor air

quality– Odours are vapours, they cannot be filtered– Catalytic converter oxidises odours to harmless levels of CO2

• Carbon monoxide (CO) may be ingested or formed by breakdown of hydrocarbons in bleed air– Catalytic converter will oxidise CO to harmless level of CO2

Catalytic

Converter

Bleed airinc. odours + CO

Bleed air

CATALYTIC CONVERTOR TECHNOLOGY AVAILABLE NOW


• Options:– Stand alone hydrocarbon converter

– Combined with ozone converter function to become Combined Hydrocarbon and Ozone Converter (CHOCTM)

– Combined ozone convertor and pre-cooler/heat exchanger

Catalytic Conversion

HC + O3 = CHOC

+ =FLEXIBILITY TO MEET THE REQUIREMENT


Aerosols in Bleed Air• Fluids and oils

– May coat ducting and air conditioning equipment

– Degraded products cause odours and CO

– Extreme cases may cause haze or smoke

• Removal of aerosolsfrom bleed air

– Impact of liquidparticles on fibres

– Will not removevapours

Bleed air + aerosol Bleed air


Photocatalyst Oxidation (PCO)Provides Low Temperature Removal of Impurities in Recirculation Air

Approach: • proprietary catalyst activated by UV lamp• buffer adsorbent to remove concentration spikes

Benefits:• permits increased level of

recirculated to outside air • disinfects viruses, bacteria

& fungal spores• removes odours & organic

compounds

ENABLES USE OF INCREASED RECIRCULATION LEVEL

Clean, low temperature air

Filter UV

Low temperature air with micro-

organisms


Bleed Air Monitor

• ground diagnostic tool to detect and locate bleed air contaminants

• real time detection of synthetic lubricants and other hydrocarbons

• catalyst converts organic hydrocarbons (VOC’s) to carbon dioxide (CO2)

• operates at 28 VDC (aircraft power compatible)

• portable device works in the ppb range (300)

• on-line monitoring

IN-FLIGHT VERSION UNDER DEVELOPMENT


Agenda



Conclusions

•The current and forecast volume of passenger flights demands that concerns are addressed•This can only be done under the control of appropriate authority•New standards are required to regulate the activity•Reduced air quality is a result of a combination of contaminated outside air and/or incorrectly operated aircraft systems•Supplementary equipments available to treat existing fleet and equip new build

Environmental Control Systems and the Cabin...

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