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In this study, two vehicles were tested under real driving conditions with gaseous exhaust emissions measured using a portable emissions measurement system (PEMS). One of the vehicles featured a hybrid powertrain with a spark ignition internal combustion engine, while the other vehicle featured a non-hybrid (conventional) spark ignition internal combustion engine. Aside from differences in the powertrain, the two test vehicles were of very similar size, weight and aerodynamic profile, meaning that the power demand for a given driving trace was very similar for both vehicles. The test route covered urban conditions (but did include driving on a road with speed limit 90 km/h). The approximate test route distance was 12 km and the average speed was very close to 40 km/h.

Non-plugin hybrids represent a technology with the capability to significantly reduce fuel consumption (FC), without any changes to refuelling infrastructure. The EU market share for this vehicle type in the passenger car segment was 3% in 2018 and this powertrain type remains of interest as an option to meet the European Union (EU) fleet average CO2 limits. EU legislative procedures require emissions limits to be met during the chassis dynamometer test and in the on-road real driving emissions (RDE) test, while official CO2/FC figures are quantified via the laboratory chassis dynamometer test only. This study employed both legislative test procedures and compared the results. Laboratory (chassis) dynamometer testing was conducted using the Worldwide Harmonised Light Vehicles Test Procedure (WLTP). On-road testing was carried out in accordance with RDE requirements, measuring the concentration of regulated gaseous emissions and the number of solid particles (PN).

This paper reviews the exhaust emissions from direct injection (DI) diesel engines in the initial period following start-up. The tests were undertake in “cold start” mode (the temperature of the cooling water and lube oil being equal to the ambient temperature) and “warm start” modes (after achieving a state of equilibrium). The results from both states are compared. Exhaust emissions in the period from cold start is very important and must be improved in order to satisfy present day standards worldwide. A significant emission decrease during cold start can be achieved by incorporating selective fuel cut-off during the few seconds directly after beginning of engine crank. Compared to the acceptable gaseous pollutant concentrations, it was observed that an almost 50% reduction in hydrocarbon emission and a 30% reduction in carbon monoxide emissions were obtained (3 minutes of idle run).

The modern solution of two-stage combustion, namely the Turbulent Jet Ignition, enables the combustion of ultra-lean mixtures. Thanks to this solution, it became possible to reduce fuel consumption and, at the same time, to increase the combustion process indicators (including the overall combustion system efficiency). The article presents the results of numerical tests of a heavy-duty engine equipped with the TJI system running on hydrogen fuel. The operating conditions of the Heavy-Duty engine at n = 1500 rpm and IMEP = 10 bar with a prechamber with 7 holes were analyzed. The research was conducted with the use of lean mixtures (global lambda ca. 2 or more). The AVL FIRE software was used to perform the analysis of different fuel doses delivered to the main chamber, with a constant global excess air coefficient value. Increasing the proportion of hydrogen in the pre-chamber resulted in its reduction in the main chamber.

The oil consumption can be considered as a source of the toxic compounds emission in internal combustion engines, The paper presents a theoretical and experimental analysis of the problem. Experimental investigation has been carried out according the European ECE R15 and ECE R49 standard tests for engines (Otto and Diesel types) of regular and doubled oil consumption. A significant increase in emission of hydrocarbons has been found for the increased oil consumption. Characteristics of the polycyclic aromatic hydrocarbons (PAH) group as well as an individual method of the PAH compounds examination have been discussed in the paper (gas freezing method and chromatography have been applied).

This paper presents a study of passenger cars in terms of emissions measurements in tests conducted under real driving conditions (RDE - Real Driving Emissions) by means of PEMS (Portable Emission Measurement System) equipment. A special feature of the RDE tests presented in this paper is that they were performed under Polish conditions and the specified parameters may differ from those in most other European Union countries. Emission correction coefficients have been defined, based on the test results, equal to the increase (or decrease) of driving emissions during the laboratory (‘chassis dyno’) test or during normal usage in relation to the EU emission standards (emission class) of the vehicle.

The article shows the results of particulate matter emissions obtained in the ESC cycle. In order to carry out the tests different devices were applied for the measurement of particular matter (AVL Smart Sampler - measurement by means of a gravimetric method of a partial exhaust smoke dilution, Horiba Mexa 1220 PM - measurement with the use of two flame ionizing detectors), which were then compared to the smokiness values (AVL 415 - measurement of exhaust smoke values, Opacimetr 439 - measurement of exhaust opacity). Having compared the obtained correlation results, main relationships of fractional composition of particular matter, obtained in the tests, were defined.

The motor vehicle is one of the main sources of pollutant emissions, especially in urban areas. Environmentally friendly fuels are regarded as very effective means to decrease emissions. With regard to diesel engines, the reduction in nitrogen oxides and particulates are major problem areas. Although the fuel influence on NOx is comparatively low, the composition and parameters of diesel fuel have a big influence on particulate emissions and composition. Sulphur content is one of fuel proprieties, which has the most considerable influence on particulates. This paper describes results of the research on particulate emissions from diesel engines fuelled with research fuels of differing sulphur content. The sulphur content of the research fuels varied from 2000 ppm through 350 ppm (EURO III) and 50 ppm (EURO IV limit, which will be in force in the European Community from 1 January 2005) up to less than 5 ppm.

A vital question for car manufacturers in countries where the temperature over night falls below freezing, is the significant increase of CO (carbon monoxide) and HC (hydrocarbon) emissions during the start and warm-up of spark ignition engines. ECE (Economic Commission for Europe) (UDC) (Urban Driving Cycle) cycles, divided into elementary phases, have been used to determine the level of harmful CO and HC emissions and fuel consumption in the cold start and warm up phase. Tests were undertaken on cars conditioned in temperatures ranging from +22°C to -15°C have shown significant increases in CO and HC as the temperature decreases.

The paper describes the research on the problem of oxygenating diesel fuel with the use of gases containing oxygen (air or diesel exhaust gas). The incentive, which encouraged the authors to exploit this idea, was a number of promising results of some earlier research on oxygenated fuel additives. The paper provides a detailed description of the system, especially the injection pump for dissolving gas in the fuel, designed and built by the authors. The paper describes also some changes in physical and chemical parameters of the fuel, which were observed while the fuel was flowing through the experimental injection system. These changes resulted from the reactions between fuel and oxygen, which were additionally reinforced by high pressure and temperature in the experimental injection system. In the further part of the article, the attention is drawn to the way the gases containing oxygen influence the exhaust emissions.

This paper reviews the exhaust emissions from direct injection diesel engines in the initial period following startup. The tests were undertake in “cold start” mode (temperature of cooling water and lube oil equal ambient temperature) and “warm start” modes (after getting equilibrium state). Both results were compared. Exhaust emissions in the period of run from cold start to warmed-up is very important to satisfy present day standards worldwide.

The great reduction in future diesel engine emission limits, especially PM and NOx, forces one to develop means to comply with stringent legislation. Environmentally friendly fuels are regarded as a very effective means to decrease emissions. Although the emission reduction is less than could be achieved by the most modern engine technology or alternative fuels, the immediate net effect of reformulated diesel fuel on emissions is significant, as it takes place over the whole vehicle population. The experimental results presented in this paper were obtained within a research program investigating the effect of different fuels upon emissions from compression-ignition automotive engines. The research were carried out in the laboratories of the BOSMAL Automotive R & D Centre in co-operation to Institute of Internal Combustion Engines at Poznan University of Technology. The partial results of this research program were presented in SAE Paper 2002-01-2219.

Due to a rapid development of air transportation there is a need for the assessment of real environmental risk related to the aircraft operation. The emission of carbon monoxide and particulate matter is still a serious threat~constituting an obstacle in the development of combustion engines. The applicable regulations related to the influence of the air transportation on the environment introduced by EPA (Environmental Protection Agency), ICAO (International Civil Aviation Organization) contained in JAR 34 (JAA, Joint Aviation Requirements, JAR 34, Aircraft Engine Emissions), FAR 34 (FAA, Federal Aviation Regulations, Part 34, Fuel Venting and Exhaust Emission Requirements for Turbine Engine Powered Airplanes), mostly pertain to the emission of noise and exhaust gas compounds, NOx in particular. They refer to jet engines and have stationary test procedures depending on the engine operating conditions.

Non-Road machines constitutes a large group of machines designed for various tasks and mainly using CI engines for propulsion. This category includes vehicles with drive systems of a maximum capacity of several kilowatts as well as with drives with a capacity of up to thousands of kilowatts depending on the purpose of the machine. Within this group, mobile machines referred to as NRMM (Non-Road Mobile Machinery) stand out. Numerous studies of scientific institutions in Europe and around the world have proven the differences between the exhaust emissions tested in type approval tests and the actual emissions in this group of vehicles. They result from differences in operating points (crankshaft speed and load) of engines during their operation. A big problem is also their considerable age and degree of wear. Approval standards themselves are less stringent than those of heavy-duty vehicles (HDVs), although the engines have similar design and performance.

The European driving cycle, deleting the first 40 seconds of idle after the start up phase, and the US FTP 75 cycle are compared in this paper. The paper presents an analysis of emission tests for CO, HC and NOx measured during tests performed on a chassis dynamometer under laboratory conditions. The tests are reviewed and the results discussed. The objective of the study was to determine the influence of the test cycle on the measured emission of CO, HC and NOx, and the changes of fuel consumption at the initial phase of engine operation. Differences in catalyst warm up rates when running NEDC, ECE + EUDC and FTP 75 cycles are demonstrated. Methods of reduction in these harmful emissions and the results of tests with new technologies targeted at the reduction of CO, HC and NOx under cold start are also discussed.

The tests related to the exhaust emissions from non-road vehicles are currently performed on a chassis dynamometer under the name of NRSC (ISO 8178) and NRTC. In light of the growing requirements related to the environment protection in transport the authors recommend determining the exhaust emissions through real vehicle operating conditions. The tests carried out under real operating conditions could be used for the process of optimization of future power trains of regular road vehicles and non-road vehicles. What is more, these tests should be taken into account in the works on the changes of the legislation related to the emission limits from combustion engines. The paper presents the results of the tests on the exhaust emissions from an agricultural harvester engine and a tractor engine in real operating conditions. The harvester operation during the test consisted in crops collection from the field and the tractor operation during the test consisted in plowing.

An increased of carbon monoxide and hydrocarbons emissions from gasoline engines in ambient temperatures at or below 0°C is a key issue, not only in Scandinavia or northern parts of the USA and Canada, but also in countries of Central and Eastern Europe. It is typical of Poland and neighbouring countries that for six to seven months (from October to April) air temperature fails to about 0°C at night, while in winter months this temperature often fails below -10 to even -20°C. Due to this, in these countries the cars are started in the morning when the engine and all other parts of the car are considerably cool. This paper presents a special climatic conditions in view of their effect on the actual exhaust emission from a car with SI engine and results of emission tests for such gaseous pollutants as CO, HC and NOx, achieved during tests performed on a chassis dynamometer according to ECE and FTP 75 cycles.

The paper presents an analysis of the emission level from a heavy-duty truck of the GVW of 12,000 kg. The exhaust emission tests were performed under actual traffic conditions in the area of Poznań. For the tests portable exhaust emission analyzers SEMTECH DS and AVL Micro Soot Sensor were used. The characteristics of the exhaust emission components have been determined in relation to the engine speed and load as well as vehicle parameters (speed and acceleration). The paper includes an analysis of the engine operating conditions as well as the range of engine speeds and engine loads. The vehicle fuel consumption was also determined through the carbon balance method. Based on the obtained values of the emission of CO, NOx and PM, the emission indexes were determined that provided information on the relation of the measured emissions to the levels specified in the EEV standard. The emissions of all the exhaust components, except NOx were lower than the EEV limits.

This paper discusses the legislative situation regarding type approval of plug-in hybrid vehicles (also known as off-vehicle charging hybrid-electric vehicles, OVC-HEV) in the range of exhaust emissions and fuel consumption. A range of tests were conducted on two Euro 6d-complaint OVC-HEVs to quantify emissions. Procedures were based on EU legislative requirements. For laboratory (chassis dyno) testing, two different test cycles and three different ambient temperatures were used for testing. Furthermore, in some cases additional measurements were performed, including measurement of emissions of particulate matter and continuous analysis of regulated and unregulated pollutants in undiluted exhaust. Consumption of electrical energy was also monitored. On-road testing was conducted on the test vehicle tested on the chassis dyno in the tests mentioned above, as well as on a second OVC-HEV test vehicle.

The paper presents the results of the investigations of an armored modular vehicle 8x8 Rosomak fitted with a diesel engine during start and warm-up. For the measurements of the toxic compounds a portable SEMTECH DS analyzer by SENSORS was used. The analyzer allowed a measurement of exhaust emission at the same time measuring the mass flow rate of the exhaust gases. The analysis of the PM emission was performed based on the measurement of the size of the particulate matter (analyzer 3090 EEPS - Engine Exhaust Particle Sizer™ Spectrometer - by TSI Incorporated) and counting of the particles (analyzer Particle Counter by AVL). The measurements of CO, HC, NOx, PM and fuel consumption have also been carried out under static conditions, during startup and at constant engine speed without engine load. For the measurement of the engine operating conditions and the fuel consumption a diagnostic vehicle system was used.