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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.

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.

Hydrogen Fuel-Cell (HFC) technology is popular in Asia (mainly Japan), the US (chiefly California) and Europe. HFC is mostly used in passenger cars and urban buses. HFC technology is also being introduced to railway transport. Hydrogen-powered trains are an attractive alternative to diesel trains, in particular on nonelectrified railways - where roughly 70% of the world’s 200 000 locomotives operate today - and in the markets of Europe and the US (together about 55 000 diesel locomotives today). Besides avoiding carbon emissions, hydrogen trains reduce noise and eliminate local emissions of NOX and particulates. Since they use significant amounts of hydrogen, the required infrastructure is limited and can be immediately utilised. Hydrogen-powered trains are already being introduced for light-rail vehicles and regional railways - such as the trams produced by the China South Rail Corporation.

There is a growing appreciation for using buses powered by alternative fuels in urban transport. Considered as such are city bus with engines fuelled with LNG and hybrid bus. This article, as shown above, provides a comparison of road exhaust emissions from three city buses: one with a CI engine fuelled with diesel fuel, and the other with a SI engine fuelled with LNG and Hybrid bus. Both vehicles (CI and LNG) conformed to Euro VI emission standard (hybrid bus EEV), and the tests were carried out in real traffic conditions. Equivocal opinions about differences in emissions from those types of buses, among others - CO2 and NOx emissions, were the underlying cause of the tests. The comparative study was carried out along the same urban routes during bus trips over the following days in similar traffic conditions. Exhaust road emission was determined based on the vehicle's curb weight and route length, and operating fuel consumption.

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).

Hydrogen is a central pillar of energy transformation required to limit global warming to two degrees. Decarbonization is an element of that transformation, which focuses primarily on the decarbonization of motor transport, particularly individual transport (passenger cars). In this case, the use of electric vehicles equipped with hydrogen fuel cells (FCEVs) is taken into consideration. In countries such as in particular Japan and the US, but also China, France, South Korea and Germany, FCEVs and hydrogen refuelling stations are presently used. Those countries are of crucial importance in the scope discussed in this article. Those countries have also adopted implementation plans, i.e. the so-called NIP for the development of hydrogenization. The construction and the operation of HRS in respective countries are essential for the development of hydrogenization of motor transport in those countries.

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.

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.

The paper describes the measurement of PM emission from an excavator engine under actual operating conditions. The exploration of the relations between the engine operating parameters and its emissions requires measurements under actual conditions of engine operation. The specificity of the emission measurements, PM in particular, requires technologically advanced measuring devices. The situation gets even more complicated when, beside the PM mass. The particle size distribution and number (PN) also need to be measured. An important technical issue is the difficulty in fitting the measurement equipment in/on the vehicle in operation (e.g. excavator), which is why the presented investigations were carried out in a laboratory under simulated operation. The laboratory technicians applied load to the engines through the excavator hydraulic system.

The paper presents results of the road tests of exhaust gas emissions of vehicles of different emission classes (Euro 4 and Euro 5, with different mileage), fuelled with compressed natural gas. The tests of exhaust emissions were conducted on parts of the road with different characteristics of the traffic intensity. For each phase of the tests, the characteristics of the test run and the value of exhaust gas emissions were determined. To measure the exhaust emission the Portable Emission Measurement System (PEMS) was used.

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.

The paper discusses the measurement of the PM emissions from non-road vehicles (a farm tractor and an excavator) under actual operating conditions. Full exploration of the relations between the operating parameters of these vehicles and their emissions requires measurements under actual conditions of their operation. The specificity of the emission measurements, PM in particular, requires technologically advanced measuring devices. The situation gets even more complicated if, beside the PM mass, we also wish to obtain the PM size distribution and particle number (PN). One of the more important technical issues is the difficulty in fitting of the measurement equipment in/on the vehicle in operation (e.g. a farm tractor). That is the reason why the investigations were carried out in a laboratory. The laboratory technicians applied load to the engines through external devices - a hydraulic system for the excavator and a brake coupled to the farm tractor power takeoff.

The paper presents the results of tests on a combustion engine of an armored modular vehicle 8x8 Rosomak under combat simulating conditions. For the measurements of the toxic compounds a portable SEMTECH DS analyzer by SENSORS was used. The analyzer allowed a measurement of toxic compounds 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 were performed under the conditions of combat simulation and in the overboost mode. Based on the obtained results, an analysis of the engine and vehicle operation was performed and the on-road and unit exhaust emissions as well as on-road and unit fuel consumption were compared.

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.

The investigations into the emissions from light-duty vehicles are carried out on a chassis dynamometer in the NEDC test in Europe and FTP75 test in the US. Such tests do not entirely reflect the real road conditions. It should be noted that the changes in the methodology of emissions testing should go in the direction where they get closer to the actual road conditions. The paper presents the road test results obtained in an urban congested areas. The analysis of the road tests results (exhaust emissions and fuel consumption) was carried out considering the road conditions (vehicle speed and acceleration). The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the exhaust emissions. For these measurements a portable SEMTECH DS analyzer by SENSORS, Particle Counter by AVL and Particle Seizer EEPS by TSI has been used.

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.

In order to measure the concentration of exhaust emissions a mobile emission testing analyzer SEMTECH DS by SENSORS Inc was used. In the study the results of the vehicle emission tests in the road conditions were presented, as this was the only way to obtain the information on real vehicle emissions. They include information on the emissivity of the vehicles in operation and deal with the real conditions of the vehicle in motion. Reliable measurement results were obtained which were verified in simulated conditions on a chassis test bed. The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the exhaust emissions. The dynamic engine properties were indirectly taken into account using all the speed range and the range of acceleration calculated for the city traffic in order to prepare a matrix of the emission intensity.

The investigations into the emissions from light-duty vehicles have been carried out on a chassis dynamometer (NEDC test in Europe and FTP75 test in the US). Such tests do not entirely reflect the real road conditions and that is why we should analyze the correlation of the laboratory versus on-road test results. The paper presents the on-road test results obtained in an urban and extra urban cycles. For these measurements a portable SEMTECH DS analyzer by SENSORS has been used. The device is an analyzer enabling an on-line measurement of the emission gases concentration in a real driving cycle under real road conditions. The road tests were performed on road portions of several kilometers each. The obtained results were compared with the results obtained for the same vehicle during the NEDC test on a chassis dynamometer. The comparative analysis was performed including the urban and extra-urban cycles.

In order to measure the concentration of exhaust a mobile analyzer SEMTECH DS by SENSORS Inc and particle matter by TSI was used. In the study the results of the vehicle emission tests in the road conditions were presented as this was the only way to obtain the information on real vehicle emissions. They include information on the emissivity of the vehicles in operation and deal with the real conditions of the vehicle motion. Reliable measurement results were obtained which were verified in simulated conditions on a chassis test bed. The obtained data were used to specify the dependence characteristics for the influence of the dynamic engine properties on the exhaust emissions. The dynamic engine properties were indirectly taken into account using all the speed range and the range of acceleration calculated for the city traffic in order to prepare a matrix of emission intensity.

Research on the influence of oxygenated diesel fuels on the PM/NOx emission trade-off was carried out with use of 11 different synthetic oxygenated compounds, representing 3 chemical groups (glycol ethers, maleates, carbonates). Each of oxygenates were evaluated as a fuel additive at a concentration of 5% v/v in the same base diesel fuel. The tests were conducted on a passenger car equipped with a common rail turbocharged diesel engine over the European cycle NEDC and US FTP-75 cycle. All the tested oxygenates caused a reduction in PM emissions and most of them caused a certain increase in NOx emissions. The changes in emissions depended on the oxygenate type and cycle. In general, the favorable and unfavorable influence of oxygenated compounds was more intensive during the NEDC, which is a softer and less transient cycle than the FTP-75. The most favorable changes in the PM/NOx emission trade-off were obtained for maleates and carbonates.