Recent applications of ADMS-Airport
Contents
• ADMS-Airport – Overview and features
• Recent applications – Air quality impact assessments – ICAO CAEP studies – Research including SNAQ project Heathrow Airport
Recent applications of ADMS-Airport
ADMS-Airport
• Comprehensive modelling tool for air quality management of airports – Incorporates all features of ADMS-Urban – Takes into account the whole range of relevant emission sources – Moving jet sources for aircraft exhausts, capturing the effect of
movement in reducing effective buoyancy of the exhaust. Particularly important in near-field dispersion from take-off ground roll
– Annual hourly profiles for detailed temporal variation • Latest version is ADMS-Airport 3.4
– EMIT 3.4 emissions inventory tool includes latest NAEI road traffic factors and aircraft engine factors from ICAO databank issue 20B
Recent applications of ADMS-Airport
Project for Sustainable Development of Heathrow
• In 2006 DfT expert panel on modelling reviewed modelling tools used for Heathrow and other airports in UK and elsewhere
• Recommendation was that ADMS-Airport be used for future modelling at Heathrow
• ADMS-Airport was used for modelling the proposed new runway and mixed-mode operation
Recent applications of ADMS-Airport
Project Sustainable Development Heathrow (PSDH)
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Hour of the day
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D LHR2-LHR8 Measured D LHR2-LHR8 ModelledA LHR2-LHR8 MeasuredA LHR2-LHR8 Modelled
• Monitoring site LHR2 is just north of eastern end of northern runway • LHR2 records a strong signature from take-off when the northern runway is
operational with take-off to the west • Chart compares modelled and measured NOx concentrations at LHR2 for
hours when there are take-offs to the west (D) and hours when there are landings to the west (A)
• Diurnal variation as well as the difference between departures and arrivals is well captured by ADMS-Airport
Recent applications of ADMS-Airport
Modelling exhaust as moving jets
Source
• Conservation of mass, momentum, heat and species • Modifications within ADMS-Airport
– Allowance for movement of jet engine sources; reduces effective buoyancy
– Allowance for impact of wake vortices on jet plume trajectory
Entrainment – depends on relative motion and
ambient turbulence – entrainment coefficients
Drag – depends on velocity perpendicular
to plume axis – drag coefficient
Recent applications of ADMS-Airport
Schematic of Jet Engine
Input: jet model requires 1. Effective exit velocity (or volume flow rate) – from mass
flow rate, thrust and fuel burn rate 2. Temperature 3. Effective exit diameter – derived from 1, 2
Recent applications of ADMS-Airport
Neutral met conditions, plume trajectory (zp) (1st), vertical spread (σz) (2nd) and zp - σz (3rd)
Plume centreline height of the jet exhaust emitted at different points along the runway during take-off
The take-off roll starts at x = 0 with the aircraft moving in the negative x-direction
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Neutral conditions, 5m/s windRelease temperature 232.4 degrees C
Vertical plume spread of the jet exhaust emitted at different points along the runway during take-offThe take-off roll starts at x = 0 with the aircraft moving in the negative x-direction
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Neutral conditions, 5m/s windRelease temperature 232.4 degrees C
Difference between plume centreline height and vertical plume spread (Zp - sigma-z) of the jet exhaust emitted at different points along the runway during take-off
The take-off roll starts at x = 0 with the aircraft moving in the negative x-direction
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Neutral conditions, 5m/s windRelease temperature 232.4 degrees C
Recent applications of ADMS-Airport
ADMS-Airport Emissions Calculator
• MATLAB-based tool that is available for use with ADMS-Airport (contact CERC for details)
• Calculates main engine emissions during landing and take-off
• Output – Trajectory and emission profiles:
(time, horizontal distance, altitude, airspeed, net thrust, emissions, fuel burn)
– ADMS-Airport input files (.air file and .hfc file)
Flight Performance Model (ECAC 29)
Calculation of: Fuel Flow (BADA) Emissions (BFFM2, FOA v3)
Performance Database (ANP)
Engine Emissions Databank (ICAO)
Air Traffic Movement Listing
Aircraft Trajectory Profiles
Aircraft Emissions Profiles
Recent applications of ADMS-Airport
Applications of ADMS-Airport (1/2)
• ICAO CAEP Models and Databases Group (MDG) – ADMS-Airport is one of the approved models
• The approved models create projections at all major airports worldwide that are used by the ICAO Assembly as the basis for decision making on environmental matters
• ADMS-Airport Emissions Calculator is a flight-performance tool for main engine emissions that is used for MDG projections
• MDG also conduct ad-hoc studies such as validation and model inter-comparison to maintain the quality of the decision support activity
– Listed in the ICAO Airport Air Quality Manual as a typical model for the “advanced” and “sophisticated” approach
Recent applications of ADMS-Airport
Applications of ADMS-Airport (2/2)
• Air quality impact assessments – Schiphol Airport
• Study for Dutch Ministry of Transport, modelling of NO2 concentrations for 2010
– Local Air Quality Management (LAQM) • Air quality review and assessment for Hillingdon and Hounslow,
Spelthorne and Slough Borough Councils, 2010 - 2013 – Airports Commission
• Used for Gatwick and Heathrow Airport submissions, and Airports Commission Air Quality Local Assessment by Jacobs
• Research & Development – EC FP7 project TEAM_Play created a tool suite for policy
assessment, with studies of hypothetical policy changes. – NERC-funded SNAQ project, led by University of Cambridge
Recent applications of ADMS-Airport
Denver
• Study for ICAO CAEP: impact of airport altitude on flight performance models used for emissions models for Local Air Quality modelling – Denver International Airport – altitude 1600m – Sea-level with ISA Standard Atmosphere – Produced departure profiles of altitude, thrust and air speed – For several aircraft including Airbus A318 and Boeing 737-300
Recent applications of ADMS-Airport
Departure Profiles: Denver versus ISA sea-level
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ADMS Departure
ISA Altitude ISA Thrust Denver Altitude Denver Thrust ISA CAS Denver CAS
A318
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B737-300
Recent applications of ADMS-Airport
SNAQ project – Heathrow Airport
• See earlier presentation by University of Cambridge • CERC’s role
– Modelling using ADMS-Airport compared against output from University of Cambridge sensor network • Hourly concentrations, identifying patterns in airport operations • Short timescale modelling, identifying signature of individual aircraft
movements • Verification against local authority / airport automatic monitoring
network – Emissions data from Ricardo-AEA inventory and detailed aircraft
activity data – Two modelling periods
• 6-month period (July to December 2012) • 2-week focus period (4th to 18th November 2012)
Recent applications of ADMS-Airport
SNAQ: 6-month period
Total NO2 concentrations
Total NOx concentrations
SNAQ 17
Recent applications of ADMS-Airport
SNAQ: Source apportionment (SNAQ 17) Total concentrations Runway Taxiing
NOx
Total NO2
Primary NO2
NOx
f-NO2 take-off = 4.5% f-NO2 taxiing = 37%
Recent applications of ADMS-Airport
SNAQ: Individual aircraft movements
• Study period identified in sensor data – 12th November 2012, 0600 – 0700 – Take-offs from 27R (south-easterly wind)
Stable background
A318
A321 A320
Recent applications of ADMS-Airport
SNAQ: Individual aircraft movements
• Model as a series of jet sources along the runway • Emissions characteristics of each jet source depends on
position along the runway
• We know this works well when take-offs are averaged over an hour
• How well does it compare to an individual take-off signature?
Recent applications of ADMS-Airport
SNAQ: Individual aircraft movements
• How can we model an individual take-off?
• ADMS-Airport outputs hourly concentrations • When modelling take-offs over an hour, emissions from take-
offs are spread over the hour – Smaller emission rates than during take-off
• Scale emissions up to the emission rate at take-off – As though the plane was constantly taking off throughout the hour – Should give a good estimate for peak concentration from take-off
Recent applications of ADMS-Airport
SNAQ: Individual aircraft movements
• How do the modelled values compare to the observed values?
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Take off time
Comparison of ADMS-Airport modelled take-off concentrations to sensor concentrations
Using detailed movements data
Sensor data Modelled data
A318
A321
A320
Recent applications of ADMS-Airport
Summary
• ADMS-Airport is a comprehensive tool for modelling air quality at airports – Widely used for modelling airports – Continues to be improved and updated – Used in research projects and ICAO CAEP studies
• SNAQ project is enhancing understanding of aircraft operations through high resolution monitoring and modelling – Patterns in long-term concentrations can be explained by
differences in emissions from different aircraft modes – Patterns in short-term concentrations show signatures of
individual aircraft – Ongoing work: evaluating emission indices based on pollutant
ratios
Recent applications of ADMS-Airport
ADMS-Airport
Thank you for listening! Any questions? Mark Jackson [email protected] cerc.co.uk/ADMS-Airport