PHEM and PEMS Data Use PHEM Passenger Car and Heavy Duty Emission Model ERMES Plenary Meeting Zurich, 14 th Nov. 2017 Stefan Hausberger I
PHEM Overview Vehicle parameters Vehicle longitudinal dynamics simulation + driver model + thermal model for catalysts F Air Chassis C d x A, mass, rot. Inertias F Acc Tires r dyn, RRC F g F Z F Roll1 Gearbox + axle loss maps i Gears, i Axle F Roll2 F Grd Engine Auxiliaries After treatment P rated full load curve Emission map Transient parameters Avg. Power demand per auxiliary Thermal capacities Functions for conversion efficencies P e = P Air + P Roll + P Acc + P Grd + P Loss + P Aux rpm = F(v,d,i) Calculation in each 1 Hz time step: Given: v, a from driving cycle Result: power and rpm at engine + dynamic parameters for dynamic corrections, temperatures and volume flows in after treatment, 2
Steps from measured emissions to emission factors Coordination of vehicle tests in EU Elaboration of Emission Factors (model development & validation) Traffic situations Registration db Average vehicle data: masses, power, etc. Emission factors Remote sensing db Supplementing emission data on large # of vehicles 3
PHEM Overview on main tasks covered PHEM development started at TUG in late 90 ies for HDVs in EU project ARTEMIS Extension from HDVs to passenger cars and LDVs for HBEFA Simulation of exhaust after treatment: used for SCR from HDVs (cool down in urban areas) for EURO V on Extension of engine emission map calculation routine to cover also PEMS tests from HBEFA 3.3 on (~50% of passenger car data already from PEMS) Hot engine emission maps separated according to ambient temperature ranges to consider thermal window effects for HBEFA 3.3 Extension to simulation HEV, PHEV and BEV (model for electric motor, battery and control strategy) in 2012 in a HBEFA project. Planned to be used in HBEFA 4.1 for PHEV and BEV fleet emission factors Extension to simulate mopeds and motorcycles in 2017 in a BAST project Planned to be used in HBEFA 4.1 for updated emission factors 2-wheelers Extension of SCR model to calculate NH3 level in SCR for low load cycles Planned to be used in HBEFA 4.1 for simulation of cycles <200 C SCR temp. Ongoing collection of test data for all vehicle categories to extend data base for engine emission maps (PHEM HBEFA 4.1 results shall be available for ERMES) 4
Database of average vehicles for Handbook Emission Factors (HBEFA) Vehicle category Propulsion technology Weight category Emission- Standard Emission control Pass car Gasoline LCV N1 I Pre EURO 1 DPF LCV Diesel LCV N1 II EURO 1 SCR Rigid truck PHEV* LCV N1 III EURO 2 EGR Tractor & trailer BEV* HDV 7.5t EURO 3 Coach HEV* HDV 7.5t - 12t EURO 4 Bus HDV 12t - 14t EURO 5 Two-Wheeler... EURO 6 EURO 6 d-temp EURO 6d *in PHEM for single vehicles but no average HBEFA vehicle data set Components: CO 2, CO, HC, CH 4, NO x, NO 2, PM, PN, N 2 O, other non regulated PEMS does not cover all relevant components! Chassis dyno still needed! 5
SCR Efficiency Institute of Internal Combustion Engines and Thermodynamics Some new features Extension of SCR model to calculate NH3 level in SCR Background: NH3 is produced from AdBlue injected in exhaust. Reaction needs ~>200 C. Long phases <200 C exhaust T strong increase of tailpipe NOx NH 3 consumption calculated from raw Nox and conversion SCR conversion rate NO+NO 2 +2 NH 3 2 N 2 + 3 H 2 O Dosing strategy targets 50% NH3 level in SCR but stops dosing <200 C SCR efficiency map (HDV) Correction of SCR efficiency + = 6
SCR model with NH 3 storage Comparison new and old model in slow city cycle for delivery truck Much better agreement with measured NOx. Open: average heating strategies from vehicles? NH3 level in SCR drops (T<200 C) SCR efficiency drops Emission map filled mainly with short cold phases average SCR efficiency quite good Underestimation of NOx in long low load cycles 7
Use of PEMS Data Institute of Internal Combustion Engines and Thermodynamics Typically no measured engine power available from ERMES labs tests Engine power calculated from generic CO2 engine maps according to engine technology from CO2 mass flow and engine speed recording engine emission maps can be filled as from engine or vehicle test stand Generic CO 2 map Engine power calculated from rpm and CO 2 Uncertainty: maps of single engines within a vehicle class differ against generic average maps +/-10% (?) Further uncertainties in simulation, auxiliary power demand, losses in transmission do not yet allow exact uncertainty assessment 8
Use of PEMS Data Institute of Internal Combustion Engines and Thermodynamics Typically no measured engine power available from ERMES labs tests Engine power calculated from generic CO2 engine maps according to engine technology from CO2 mass flow and engine speed recording engine emission maps can be filled as from engine or vehicle test stand Generic CO 2 map Engine power calculated from rpm and CO 2 Uncertainty: maps of single engines within a vehicle class differ against generic average maps +/-10% (?) Further uncertainties in simulation, auxiliary power demand, losses in transmission do not yet allow exact uncertainty assessment 9
Effect of ambient temperature on NOx emissions PEMS tests covered -3> to +33 C Different routes and driver behaviour in PEMS tests overlap the effect of the ambient temperature. To analyse the ambient temperature effect on NOx isolated maps for different temperature ranges were created by PHEM. By simulating a common cycle (CADC) a basis for the analysis was created. PHEM with PEMS data Good agreement with Remote Sensing EURO 6 diesel cars: 40 % to 50 % Nox from 20 to 10 C 10
Recommendations Simulation based approach for emission factors has advantages: User can change update uncertain data later for all vehicles: driving cycles vehicle loadings gear shift behaviour Temperature distributions Cold starts Etc. Saving measured data in engine emission maps proved to be a useful approach. Influences not covered by P and rpm become more relevant with recent technologies (catalyst temperature, NH3 level, battery SOS for HEV, PHEV, etc.) and need to be considered in further model parameters. Storing test data in data base in instantaneous format ensures to be able to extend models in future if needed. Chassis dyno tests are useful to get information on non regulated pollutants, to check PEMS system! And is better solution for some tasks (e.g. Temp. effects) 11
WG EFs and measurements: Ongoing and planned national measurement activities 12
Data collection activities ERMES labs contacted regularly to get information on tests (executed and planned) Overview on vehicle tests collected in Excel sheet Check before vehicle selection for test campaigns to avoid double testing Check fleet coverage to allocate funds to vehicle categories with low coverage Vehicle class ERMES lab Test type (Chassis / PEMS) EURO class Vehicle Make Vehicle Model Techology/Fuel Engine capacity [l] legislative real world (planned / finalised) Expected date of data availability pass. car ADAC Chassis 5 Citroen C4 Picasso HDi 150 FAP Exclusive diesel 1,4-<2L yes yes finalised pass. car ADAC Chassis 6 MAZDA CX-5 SKYACTIV diesel 1,4-<2L yes yes finalised pass. car ADAC Chassis 5 Opel Insignia 2.0 BiTurbo CDTI ecoflex Start&Stop diesel 1,4-<2L yes yes finalised pass. car ADAC Chassis 5 Skoda Fabia Combi 1.2 TSI Elegance petrol <1,4L yes yes finalised pass. car ADAC Chassis 5 VW PASSAT VARIANT 2,0 TDI BMT diesel 1,4-<2L yes yes finalised pass. car EMPA Chassis 6 Alfa Romeo Giulietta 1.4 petrol 1,4-<2L yes yes finalised March 2016 pass. car EMPA Chassis 5 BMW 118d diesel >=2L yes yes finalised already available pass. car EMPA Chassis 5 BMW 125i Coupe petrol SUV (>2L) yes yes finalised already available pass. car EMPA Chassis 6 BMW 428i petrol >=2L yes yes finalised March 2016 pass. car EMPA Chassis 6 BMW 530d Xdrive diesel >=2L yes yes finalised End of 2015 pass. car EMPA Chassis 6 BMW X3 xdrive20d diesel >=2L yes yes planned (Nov 2015) March 2016 pass. car EMPA Chassis 5 Citroen C5 3.0 V6 Hdi diesel SUV (>2L) yes yes finalised already available Tested vehicles collected from EURO 5 on: 238 passenger cars 31 LCVs 92 HDVs 104 2-wheelers (all Emission classes) 13
Data collection activities: passenger cars Analysis from EURO 5 on: Only 3 GDI? Makes are not covered in representative way yet E.g. 75 EURO 6 diesel cars measured 30 of them BMW and VW If tests are still ongoing: please check what has already been tested! EURO 6 diesel Total vehicles Alfa Audi 5 BMW 16 Chevrolet Chrisler Citroën 1 Daimler 5 Fiat Ford 3 Honda Hyundai JLR Kia 1 MAZDA 8 Mini 1 Mitsubishi Nissan 1 Opel 4 Peugeot 7 Porsche 1 Renault 6 Seat Skoda Ssangyoung Subaru Suzuki Toyota 2 Volkswagen 14 Volvo 14
Data collection activities: LCVs Analysis from EURO 5 on: 10 with SEMS only EU6 LCV models covered Mercedes Sprinter Renault Traffic dci 145 Ford Transit Mercedes Benz Vito 119BT 4x4 Citroen Jumpy SpaceTourer VW T6 Kombi TDI 4M Iveco Daily 35 Missing: Citroen, Fiat, Opel, Peugeot 15
Data collection activities: HDVs Analysis from EURO VI on: Makes from EU VI tests No. Of vehicles DAF 1 MAN 5 IVECO 2 MB 3 Scania 1 Volvo 12 EURO VI mainly covered by PEMS tests from AVL Sweden and from TUG New method in PHEM to convert PEMS into engine maps should be applicable for all data. 16
Data collection activities: 2-wheelers Reasonable number of 2-wheelers tests seems to be available for an update of emission factors with PHEM. Data quality unclear yet. TUG will analyse data for HBEFA project. further and try to elaborate emission factors. Number of Euro 4 tests yet quite low. Total Veh. <50 ccm <125ccm >125ccm EURO 2 24 10 n.a. n.a. EURO 3 28 4 6 18 EURO 4 6 0 1 5 17
Coordination of test activities Paper describing default settings for road loads etc. for chassis dyno tests as well as proposed test cycles available for cars and LCVs. For 2-wheelers such a proposal is under preparation. For PEMS the recommendation is to follow the ISC regulations. Engine speed has to be recorded to produce engine maps! Data handling: Information on ongoing and planned tests: TUG, Stefan Hausberger Measured data per vehicle: Infras, Mario Keller Standard form for reporting in MS Excel exist 18
Thank you for your attention! Contact & Information Univ.-Prof. Dr. Stefan Hausberger: Email: hausberger@ivt.tugraz.at Tel: +43 316 873 30260 Dr. Martin Rexeis Email: rexeis@ivt.tugraz.at Tel: +43 316 873 30270 Graz University of Technology Institute of Internal Combustion Engines and Thermodynamics http://www.ivt.tugraz.at/ I