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Particle number (PN) emission limits were introduced in the European Union’s regulations for light-duty and heavy duty vehicles in the years 2011-2014. Since then, PN measurements have become a common practice in the automotive sector. Many studies showed that the current methodology, which counts particles >23 nm, misses a large fraction of particles for some engine technologies, such as port fuel injection vehicles or vehicles fueled with compressed natural gas (CNG). However, data for the latest technology vehicles are lacking. For this reason, we measured PN emissions >23 nm and >10 nm of >30 CNG, gasoline and diesel-fueled vehicles. Two systems were measuring in parallel from the full dilution tunnel; one with an evaporation tube and the other with a catalytic stripper. The PN emission levels spanned over three orders of magnitude depending on whether there was a particulate filter installed or not.

The aim of this paper is to analyse the results of regulated and unregulated emissions and carbon dioxide (CO2) emissions of passenger cars equipped with compression-ignition engines that meet the emission Euro 6d standards. Both test vehicles featured selective catalytic reduction (SCR) systems for control of oxides of nitrogen (NOx) and one vehicle also featured a passive NOx absorber (PNA). Research was performed using the current European Union exhaust emission test methods for passenger cars (Worldwide harmonized Light vehicles Test Procedures (WLTP)). Emission testing was performed on a chassis dynamometer, within a climatic chamber, at two different ambient temperatures: 23°C (i.e. Type I test) and -7°C (known as a Type VI test - currently not required for this engine type according to EU legislative requirements).

Vehicular ammonia emissions are currently unregulated, even though ammonia is harmful for a variety of reasons, and the gas is classed as toxic. Ammonia emissions represent a serious threat to air quality, particularly in urban settings; an ammonia emissions limit may be introduced in future legislation. Production of ammonia within the cylinder has long been known to be very limited. However, having reached its light-off temperature, a three-way catalyst can produce substantial quantities of ammonia through various reaction pathways. Production of ammonia is symptomatic of overly reducing conditions within the three-way catalyst (TWC), and depends somewhat upon the particular precious metals used. Emission is markedly higher during periods where demand for engine power is higher, when the engine will be operating under open-loop conditions.

Diesel (compression ignition, CI) engines are increasingly exploited in light-duty vehicles, due to their high efficiency and favorable characteristics. Limited work has been performed on CI cold-start emissions at low temperatures. This paper presents a discussion and a brief literature review of diesel cold-start emissions phenomena at low ambient temperatures and the results of tests performed on two European light-duty vehicles with Euro 5 CI engines. The tests were performed on a chassis dynamometer within an advanced climate-controlled test laboratory at BOSMAL Automotive Research and Development Institute, Poland to determine the deterioration in emission of gaseous (HC, CO, NOx, CO2) and solid (PM, PN) pollutants following the EU legislative test procedure (testing at 20°C to 30°C and at -7°C, performed over the NEDC). The tests revealed appreciable increases in emissions of regulated pollutants.

Spark ignition (SI) engines are susceptible to excess emissions at low ambient temperatures. Direct injection leads to the formation of particulate matter (PM), and direct injection spark ignition (DISI) engines should show greater PM emissions at low ambient temperatures. This study compares excess emissions of gaseous and solid pollutants following cold start at a low ambient temperature and the standard test temperature. Euro 5 passenger cars were tested on a chassis dynamometer within BOSMAL's climate-controlled test chamber, according to European Union legislation (−7°C over the urban driving cycle (UDC), and at 25°C). Two vehicles were also tested over the entire New European Driving Cycle (NEDC). Emissions of regulated compounds and carbon dioxide were analyzed; particulate emissions (both mass and number) were also measured, all using standard procedures.

Direct injection gasoline engines have been gaining popularity for passenger car applications, particularly in the EU. It is well known that emissions of particulate matter are an inherent disadvantage of spark ignition engine with direct injection. Direct injection of gasoline can lead to the formation of substantial numbers of particulates, a proportion of which survive to be emitted from the vehicle's exhaust. EU legislation limits particle mass (PM) emissions; particle number (PN) is soon to be limited, although an opt-out means that dedicated filters will not be required immediately. A range of tests were conducted on a pool of Euro 5 passenger cars in BOSMAL's climate controlled emissions laboratory, using EU legislative test methodology. In addition, further measurements were performed (particle size distribution, tests at multiple ambient temperatures).

Ethanol has long been a fuel of considerable interest for use as an automotive fuel in spark ignition (SI) internal combustion engines. In recent years, concerns over oil supplies, sustainability and geopolitical factors have lead multiple jurisdictions to mandate the blending of ethanol into standard gasoline. The impact of blend ethanol content on gaseous emissions has been widely studied; particulate matter emissions have received somewhat less attention, despite these emissions being regulated in the USA. Currently, in the EU particulate matter emissions from SI engines are partially regulated - only vehicles featuring direct injection SI engines are subject to emissions limits. A range of experiments was conducted to determine the impact of fuel ethanol content on the emissions of solid pollutants from Euro 5 passenger cars.

The paper evaluates the possibility of using different biodiesel blends (mixture of diesel fuel and Fatty Acid Methyl Esters) in modern Euro 4/ Euro 5 direct-injection, common-rail, turbocharged, light-duty diesel engines. The influence of different quantity of RME in biodiesel blends (B5, B20, B30) on the emission measurement of gaseous pollutants, such as: carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NOx), carbon dioxide (CO2) and particulate matter (PM) for light-duty-vehicle (LDV) during NEDC cycle on the chassis dynamometer as well as engine performance and reliability in engine dyno tests were analysed. All test results presented have been to standard diesel fuel. The measurement and analysis illustrate the capability of modern light-duty European diesel engines fueled with low and medium percentages of RME in biodiesel fuel with few problems.

The use of biofuels (biodiesel and gasoline-alcohol blends) in vehicle powertrains has grown in recent years in European Union, the United States, Japan, India, Brazil and many other countries due to limited fossil fuel sources and necessary reduction of anthropogenic CO2 emissions. European car manufacturers have approved up to 5 percent of biodiesel blend in diesel fuel (B5 biodiesel blend) which meets European fuel standards EN 14214 and EN 590. The goal for research is to achieve higher biodiesel content in diesel fuel B10 and B20, without resorting to larger diesel engines and fuel feed system modernization. This paper evaluates the possibility of using higher FAME content in biodiesel blends (mixture of diesel fuel and Fatty Acid Methyl Esters) in modern Euro 4 vehicle with direct-injection, common-rail and turbocharged light-duty diesel engine with standard engine ECU calibration and standard injection equipment (not tuned for biodiesel).

This paper reports testing conducted on multiple vehicle types over two European legislative driving cycles (the current NEDC and the incoming WLTC), using a mixture of legislative and non-legislative measurement devices to characterise the particulate emissions and examine the impact of the test cycle and certain vehicle characteristics (engine/fuel type, idle stop system, inertia) on particulate emissions. European legislative measurement techniques were successfully used to quantify particle mass (PM) and number (PN); an AVL Microsoot sensor was also used. Overall, the two driving cycles used in this study had a relatively limited impact on particulate emissions from the test vehicles, but certain differences were visible and in some cases statistically significant.

Cold starts are demanding events for spark-ignition (SI) internal combustion engines. When the temperatures of the engine oil, coolant and the engine block are close to the ambient temperature, start-up can be difficult to achieve without fuel enrichment, which results in significant excesses in exhaust emissions and fuel consumption. In general, the lower the ambient temperature, the more substantial these problems are. Many nations frequently experience sub-zero ambient temperatures, and the European Union (among others) has specified an emissions test at low ambient temperature (-7°C). Passenger cars typically experience one to two cold start events per day, and so both cold starts and the warm-up period that follows are significant in terms of exhaust emissions. This paper examines emissions at low ambient temperatures with a special focus on cold start; emissions are also compared to start-up at a higher ambient temperature (24°C).

The aim of this study was to evaluate the accuracy and precision of measurements of an automatic weighing system used to assess the mass emission of particulate matter emitted by internal combustion engines. Thirty test cycles were carried out for cars equipped with spark-ignition and compression-ignition engines that met the Euro 4, Euro 5 and Euro 6 emission standards. Exhaust gas samples for analysis were taken according to EU 2017/1151 recommendations for driving cycles performed on AVL and Zöllner chassis dynamometers, AVL-CVS i60 LD LE and HORIBA-CVS 7400 S exhaust-gas collection systems, WLTC driving cycle according to EU 2017/1151, NEDC according to UNECE No. 83, RDE, RTS and TFL cycles, non-standard cycles of car manufacturers. The mass emission of particulate matter was measured using Teflon-coated glass filters of Pallflex® Emfab™ type TX40HI20WW, which ranged between 96 ÷ 102 mg.

Ethanol has a long history as an automotive fuel and is currently used in various blends and formats as a fuel for spark ignition engines in many areas of the world. The addition of ethanol to petrol has been shown to reduce certain types of emissions, but increase others. This paper presents the results of a detailed experimental program carried out under standard laboratory conditions to determine the influence of different quantities of petrol-ethanol blends (E5, E10, E25, E50 and E85) on the emission of regulated and unregulated gaseous pollutants and particulate matter. The ethanol-petrol blends were laboratory tested in two European passenger cars on a chassis dynamometer over the New European Driving Cycle, using a constant volume sampler and analyzers for quantification of both regulated and unregulated emissions.

Particulate matter in vehicular exhaust is now under great scrutiny. In the EU, direct injection spark ignition (DISI) engines running on petrol now have limits for particulate emissions set for both mass and number. Current legislative test procedures represent a best-case scenario - more aggressive driving cycles and lower ambient temperatures can increase particulate emissions massively. Ambient temperature is generally the environmental parameter of most importance regarding particulate emissions from an engine, particularly for the reasonably brief periods of operation typical for passenger cars operating from a cold start. Two Euro 5 vehicles with DI SI engines were laboratory tested at three ambient temperatures on two different commercially available fuels, with particulate emissions results compared to results from the same fuels when the vehicles were tested at 25°C.