Traffic Emission modelling

Transcription

1 Institut for Internal Combustion Engines and Thermodynamics Section Traffic and Environment Traffic Emission modelling Ulrich Uhrner, Martin Rexeis, Stefan Hausberger

2 Outline traffic emissions AIM: computation for an entire street network Emission General Approach: E i = EF i A i Determination of Emission Factors (EF) A i traffic Activity data Effect of emissions Allocation of emissions to road sections in space 3-d problem! + time (of release) 4-dim! Garmisch,

3 Determination of Emission Factors (EF) Multitude of important parameter Different vehicle concepts (car, coaches, tractor trailer, ) Engine & fuel concepts (diesel, gasoline, ) Engine sizes and vehicle weights Different traffic situations: Motorway, minor roads average speed Constant, congested, stop & go, transient dynamics Emission standards ( Euro 3, Euro 4, ; EURO V ) Impossible measurements on 100s of vehicles & cyles! Measurements on a representative number of vehicles & engines as well as cycles required Use measurements & physics in appropriate & efficient way and model the problem! Garmisch,

4 Methodology emission modelling Microscale Emission model PHEM Driving resistances & transmission Emission Map losses NOx[(g/h)/kW_ratedpower] Pe/P_rated n_norm 1.0 Gear shift model Fuel Quality chassis dyno (2-wheeler, cars, HDV) Subroutines Engine load, FC, emissions Transient Correction Cold start tool PEMS tests EFs (t) but impractical for street networks Averaging + dynamic parameters for traffic situations Garmisch,

5 NEMO NEtwork Emission Model drop out - propabilities specific annual mileage Module: Fleet layers: vehicle / engine concept / size / emission standard / exhaust aftertreatment registration - statistics vehicle stock per layer share total mileage per layer f i [%] Driving cycle parameter Vehicle specifications emission factors E i [g/km] Module: Emissions cycle-average normalised engine power Pe i [%] Specific emission data Module: Road Network road network data overall emissions resp. results per road section per vehicle layer section veh-cat Σ ( Σ E i * f i )* ADT j *L j j i ADT j... average daily traffic volume [#veh/day]... length of section [km] L j Garmisch,

6 Traffic Activity Data i.e. Vorarlberg/Feldkirch 41 traffic count stations Motorway / A-roads only For modelling higher ranked roads & base cases & simple scenarios traffic counts in Vorarlberg sufficient But NOT for small areas with lower ranked roads! Garmisch,

7 Traffic Activity Data i.e. Feldkirch urban planning Only 2 traffic count stations! For street networks detailed surveys or traffic modelling necessary Collaboration traffic planners Garmisch,

8 Traffic Activity Data from Traffic Modelling i.e. Vorarlberg/Feldkirch Differences in Annual Daily Traffic Volume [vehicles / day] Garmisch,

9 Spatial Allocation of traffic emissions to road sections Usually traffic data given as: ADTV, Shares (cars, LDV, HDV ), avg speed & evtl further details But only from Knot to Knot Shape of the road polygon GIS Otherwise manually digitizing & allocation 3rd dimension: slopes, height of dams & bridges Garmisch,

10 Example Klagenfurt Traffic modelling with VISUM & GIS interface road sections Semi-Automated processing Entire emission computation few hours with NEMO Garmisch,

11 Traffic Modelling GIS & NEMO Example Klagenfurt Application of VISUM with GIS Interface Application of NEMO Garmisch,

12 Impact of slope - motorway DTV 25,000 up / 25,000 down, HDV 16 %, speed fct (slope / max P), selected speed 130 km/h, 80 km/h) Total Emissions [kg/km] NOx [kg/km] PM10-tot [kg/km] HC [kg/km] 0 0% +/- 2% +/- 3% +/- 4% +/- 5% +/- 6% Slope [%] Garmisch,

13 Time of emission release! All Vehicles HDV LDV CARS Weight [1] Hour of the day From traffic count data derived cycles for different vehicle types & road types OR modelled data each hour Garmisch,

14 To finalize annual mean PM10 Klagenfurt Traffic exhaust Traffic non-ex Dom. heating Trade/Industry % observed [µg/m³] y = 1.00x R 2 = % % calculated [µg/m³] 0.3% 5.9% 9.6% Garmisch,

15 Thank you for your attention! Garmisch,