Cold Start Emissions of Spark-Ignition Engines at Low Ambient Temperatures as an Air Quality Risk

Open access

Abstract

SI engines are highly susceptible to excess emissions when started at low ambient temperatures. This phenomenon has multiple air quality and climate forcing implications. Direct injection petrol engines feature a markedly different fuelling strategy, and so their emissions behaviour is somewhat different from indirect injection petrol engines. The excess emissions of direct injection engines at low ambient temperatures should also differ. Additionally, the direct injection fuel delivery process leads to the formation of PM, and DISI engines should show greater PM emissions at low ambient temperatures. This study reports on laboratory experiments quantifying excess emissions of gaseous and solid pollutants over a legislative driving cycle following cold start at a low ambient temperature for both engine types. Over the legislative cycle for testing at -7°C (the UDC), emissions of HC, CO, NOx and CO2 were higher when tested at -7°C than at 24°C. Massive increases in emissions of HC and CO were observed, together with more modest increases in NOx and CO2 emissions. Results from the entire driving cycle showed excess emissions in both phases (though they were much larger for the UDC). The DISI vehicle showed lower increases in fuel consumption than the port injected vehicles, but greater increases in emission of HC and CO. DISI particle number emissions increased by around 50%; DISI particle mass by over 600%. The observed emissions deteriorations varied somewhat by engine type and from vehicle to vehicle. Excesses were greatest following start-up, but persisted, even after several hundred seconds’ driving. The temperature of the intake air appeared to have a limited but significant effect on emissions after the engine has been running for some time. All vehicles tested here comfortably met the relevant EU limits, providing further evidence that these limits are no longer challenging and need updating.

[1] Andrews, G.E., et al. (2005). Influence of Ambient Temperature on Cold-start Emissions for a Euro 1 SI Car Using In-vehicle Emissions Measurement in an Urban Traffic Jam Test Cycle, SAE Technical Paper: 2005-01-1617, DOI:10.4271/2005-01-1617.

[2] Andrews, G.E., et al. (2004). The Effect of Ambient Temperature on Cold Start Urban Traffi c Emissions for a Real World SI Car, SAE Technical Paper: 2004-01-2903, DOI:10.4271/2004-01-2903.

[3] Bielaczyc, P. & Merkisz, J. (1998). Cold Start Emissions Investigation at Different Ambient Temperature Conditions. SAE Technical Paper: 980401, DOI:10.4271/980401.

[4] Bielaczyc, P., Szczotka, A. & Woodburn, J. (2012). Excess Emissions and Fuel Consumption of Modern Spark Ignition Passenger Cars at Low Ambient Temperatures, SAE Technical Paper, 2012-01-1070, DOI:10.4271/2012-01-1070.

[5] Bielaczyc, P., Szczotka, A. & Woodburn, J. (2011). Development of vehicle exhaust emission testing methods – BOSMAL’s new emission testing laboratory, Combustion Engines. 1, 144, 3–12.

[6] Bielaczyc, P., Szczotka, A. & Woodburn, J. (2011). The effect of a low ambient temperature on the cold-start emissions and fuel consumption of passenger cars. Journal of Automobile Engineering, 225, 9, 1253–1264, DOI:10.1177/0954407011406613.

[7] Cook, R., et al. (2007). Impact of Underestimating the Effects of Cold Temperature on Motor Vehicle Start Emissions of Air Toxics in the United States, Journal of the Air & Waste Management Association, 57, 12, DOI: 10.3155/1047-3289.57.12.1469.

[8] Dardiotis, C., et al. (2012). JRC’s contribution to the revision of the European type approval procedure for light-duty vehicles. Current and Future Trends in Automotive Emissions, Fuels, lubricants and Test Methods – 2012, proceedings from the 3rd International Exhaust Emissions Symposium, 24–25 May 2012, Bielsko-Biala, Poland, Combustion Engines, 2, 149.

[9] Heywood, J.B. (1988). Internal Combustion Engine Fundamentals, McGraw-Hill, New York 1988.

[10] Joumard, R. & Serie, E. (1999). French National Institute for Transport and Safety Research, Report LTE 9931, available from http://www.inrets.fr.

[11] Joumard, R. & Serie, E. (2005). French National Institute for Transport and Safety Research, Report LTE 0509, available from http://www.inrets.fr.

[12] Laurikko, J. (1995). Ambient temperature effect on automotive exhaust emissions: FTP and ECE test cycle responses. The Science of the Total Environment, 169, 195–204.

[13] Laurikko, J. (2008). Cold-Start Emissions and Excess Fuel Consumption at Low Ambient Temperatures – Assessment Of EU2, EU3 and EU4 Passenger Car Performances. FISITA paper: F2008-06-049.

[14] Smokers, R., et al. (2004) Expert judgement on the long term possibilities of conventional emission abatement technologies for passenger cars, Topics in Catalysis, 30/31, 439–443, DOI: 10.1023/B:TOCA.0000029787.60870.49.

[15] Tribulowski, J., et al. (2002). Influence of Atomization Quality on Mixture Formation, Combustion and Emissions in a MPI-Engine Under Cold-Start Conditions, Part II. SAE Technical Paper: 2002-01-2806, DOI: 10.4271/2002-01-2806.

[16] UNECE Regulation no 83 – Annex 8.

[17] Vehicles in use: key figures (2008). ACEA (European Automobile Manufacturers' Association), available from http://www.acea.be.

[18] Weilenmann, M., et al. (2005). Regulated and nonregulated diesel and gasoline cold start emissions at different temperatures, Atmospheric Environment, 39, 2433–2441, DOI: 10.1016/j.atmosenv.2004.03.081.

[19] Weilenmann, M., et al. (2009). Cold-start emissions of modern passenger cars at different low ambient temperatures and their evolution over vehicle legislation categories, Atmospheric Environment, 43, 2419–2429, DOI: 10.1016/j.atmosenv.2009.02.005.

[20] Weilenmann, M., et al. (2013). The cold start emissions of light-duty-vehicle fl eets: A simplified physics-based model for the estimation of CO2 and pollutants, Science of The Total Environment, DOI: 10.1016/j.scitotenv.2012.11.024.

[21] Bielaczyc, P. & Szczotka, A. (2007). Analysis of Uncertainty of the Emission Measurement of Gaseous Pollutants on Chassis Dynamometer, SAE Technical Paper 2007-01-1324, DOI: 10.4271/2007-01-1324.

[22] Żak, M. & Konieczyński, J. (2008). Comparison of benzene and its alkylated derivatives profiles in car’s fuels, engines exhaust gases and in air in vicinity of communication arteries, Archives of Environmental Protection, 34, 2, 3–11.

Archives of Environmental Protection

The Journal of Institute of Environmental Engineering and Committee of Environmental Engineering of Polish Academy of Sciences

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