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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.

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.

Hybrid powertrains are replacing conventional combustion drives at an accelerating rate, while offering a reduction in fuel consumption and toxic exhaust emissions. The large share of hybrid solutions in engine vehicles has been observed for the compact class and in SUVs. The Authors of this study proposed an energy flow assessment in the hybrid powertrain system of an SUV in various driving conditions: urban, extra-urban and motorway. The tests were performed in accordance with the stipulations of the RDC test conditions and its requirements. The tests were carried out on a Toyota RAV4 HEV equipped with a 2.5 dm3 engine in a hybrid drive system along with Li-Ion batteries, which had an energy capacity of 1.11 kWh (4.3 Ah). The research was carried out on an urban route in Poznan as well as in its vicinity using three drive modes of the drive system: Eco, Normal and Sport.

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.

The article describes issues related to the impact of transport means on the environment. These issues are currently very popular due to the increasing public awareness of the negative environmental and health effects associated with air pollution. The authors estimated specific emissions in passenger-kilometers, considering a domestic travel by air and road transport. The analyzed route is located between the Polish cities: Gdansk and Cracow. The selected route is long by domestic travel standards, but in that travel distance, the road transport is still competitive to the air transport. Selected means of transport belong to popular representatives in their classes. As a road vehicle, the authors selected a modern passenger car powered by a spark ignition engine, meeting the Euro 6 emission standard. Among the passenger aircrafts, an object which belongs small jet aircrafts, propelled with Rolls-Royce Tay 611C jet engines was selected.

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.

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 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.

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.

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.

In order to measure the concentration of toxic compounds a mobile analyzer for toxic tests 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 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 harmful compound 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.

This paper reviews the emissions from direct injection (DI) diesel engine in the initial period of controlled engine operation following start-up. The tests were undertaken in „cold start” mode (temperature of cooling water and lube oil equal to ambient temperature) and „warm start” mode* (after attaining a state of equilibrium). Both results were compared.

The article is an investigation into the exhaust emission impact of operating a shunting locomotive SM42 and a track diagnostics machine UPS-80-001. The comparison of the two vehicles makes it possible to estimate the overall environmental costs of two different types of rail vehicles operating at their typical work parameters. This was done using selected exhaust emission indicators. It is used to indicate the need for further improvement in vehicle ecology such as hybrid or electric systems. Other solutions are investigated as forms of mitigating the ecological impact of operating such vehicles in or near human population centers.

The aim of this work was a preliminary discernment of the possibility of application of Pd-Au-Ag-Ni-Co (non Pt) nanometric, powder alloy as an active part of a new PM filter. The hollow part structure of TiO2-x-RuO2-x has been proposed as the active layer on the catalyst support, composed of SiC. This structure is used in the catalyst technology. The washcoat of TiO2-x-RuO2-x has been obtained by the Flame Spray Pyrolysis Deposition method (FSPD). The influence of the preparation conditions such as: flow velocity, salt concentration, temperature and process atmosphere on the size and shape of TiO2-x-RuO2-x particles has been determined. The catalyst alloy contains nanoparticles of Pd-Au, which encapsulated the nanoparticles of Ag and Ni. Such prepared nano-particles containing noble metals or metals 4d (Ni, Co, Ag), show high tolerance to sulfur and good reversible properties. The atoms of Pd prefer five coordinated sites of Ti for adsorption.

One of the main issues in the development of diesel engines is the NOx emission while the chief cause for such emission is high nitrogen content in the air and high temperature of combustion. There is a variety of methods to reduce this particular emission. One of the most widespread is exhaust gas recirculation and one of the most recent is the application of Adblue additive into the exhaust gases as a reducing agent. There are also catalytic converters capable of reducing the said emission but their efficiency is as yet insufficient. One of the more daring related concepts is the elimination of nitrogen from the air supplied to the combustion chamber through the application of ceramic ionic conductors. The technology applied in the last method is a dynamically advancing trend in material engineering. The development in this field indicates that, soon, an oxygen generator useful in the automotive engineering will become a reality.

This paper discusses the importance of the inclusion of emissions from the cold start event during legislative on-road tests on passenger cars (RDE - real driving emissions tests conducted under real-world driving conditions, as defined by EU legislation). Results from a recently-registered gasoline-powered vehicle are presented, with the main focus on the comparison of exhaust emission results: excluding/including the cold start during the initial phase of the RDE test. Cold start is the most challenging aspect of emissions control for vehicles with spark ignition engines and the inclusion of the cold start event in RDE test procedure has wide-ranging implications both for the testing process and compliance with RDE legislation via optimisation of aftertreatment systems and the engine calibration. In addition to some theoretical arguments, the results of an RDE-compliant test performed using the aforementioned procedures are presented.